Context:In irrigated agriculture,the salt stress is a major problem due to accumulation of salt from the irrigation water in the soil layers.Objectives:The aim of this study is to determinate the effect of salinity on...Context:In irrigated agriculture,the salt stress is a major problem due to accumulation of salt from the irrigation water in the soil layers.Objectives:The aim of this study is to determinate the effect of salinity on some agromorphological traits and seed nutritional quality of three sesames(Sesamum indicum L.)varieties.Methodology:This is how four solutions of different NaCl concentrations from 0,60,120 to 240 mM were used to water sesame plants at the five-leaves stage and this for two months in completely randomized device with four repetitions.Results:The results show a negative effect of the salinity growth and yield parameters,mineral elements,ascorbic acid(to 21.4% in White cultivar,28% in Brown and 24.2% in Black cultivar from 0 to 240 mM NaCl),oil(to 22.6%in White cultivar,32% in Brown and 25.5% in Black cultivar from 0 to 240 mM NaCl)and accumulation of Na(Sodium)content(to 11.8% in White cultivar,15.3% in Brown and 12.2% in Black cultivar from 0 to 240 mM NaCl),osmolytes as proteins(to 14.5% in White cultivar,11.5% in Brown and 9.6%in Black cultivar from 0 to 240 mM NaCl)and antioxydants components.Varieties White and Brown were less affected by salinity.Conclusion:White variety exhibited higher adaptive potential under salinity stress when compared to Brown variety(rich in fiber)and closely followed by Black variety.Thus White variety could be recommended for consumer oil,minerals and proteins.As for Black variety,it could be used,as glucid and antioxydants additives in food.展开更多
Bacterial wilt(BW)caused by Ralstonia solanacearum is a wide-spread and serious disease in peanut.To date,this soilborne disease could only be effectively controlled by planting resistant peanut cultivars.However,the ...Bacterial wilt(BW)caused by Ralstonia solanacearum is a wide-spread and serious disease in peanut.To date,this soilborne disease could only be effectively controlled by planting resistant peanut cultivars.However,the relatively lower yield potential of the available BW-resistant peanut cultivars is a key reason restricting productivity in most epidemic regions naturally infested with the pathogen.Even small pods or seeds and low number per plant has been regarded as the key factor for the low yield potential both in BW-resistant peanut germplasm lines and available released cultivars,whether the resistance is closely linked with key yield components remains unclear.In this study,the relationship between pod weight and BW resistance was analyzed by using a recombinant inbred lines(RIL)population derived from a crossing combination between a high yielding cultivar Xuhua 13 and a BW-resistant cultivar Zhonghua 6.From the experiments,it was found that the BW resistance was not significantly correlated with pod number per plant(PNP),hundred pod weight(HPW)and pod weight per plant(PWP)in the RIL population.Based on linkage analysis,the quantitative trait locus(QTL)s related to PNP were identified on A06,A07,A08 and B03.The QTLs for HPW were detected on A05 and A07,and the QTLs for PWP were on A06,A07 and B03.However,the QTL for BW resistance identified on B02.These results indicated that the BW resistance and the pod number per plant as well as pod weight were inherited independently.Two recombined lines(QT0944 and QT1028)with high level BW resistance and large pods(hundred pod weight over 185g)were identified from the RILs,and they possessed the favored alleles of identified QTLs from both parents,which could be used in peanut breeding for high yield and high level disease resistance.展开更多
Herbicide safeners alleviate herbicide toxicity while preserving weed-control efficacy in common buckwheat.A three-year field experiment was performed to measure the effects of quizalofop-P-ethyl(QPE)alone or in combi...Herbicide safeners alleviate herbicide toxicity while preserving weed-control efficacy in common buckwheat.A three-year field experiment was performed to measure the effects of quizalofop-P-ethyl(QPE)alone or in combination with gibberellin or brassinolide on soil enzyme activity and yield components in common buckwheat.The herbicide-brassinolide application yielded the greatest increases in soil enzyme activity and yield components without sacrificing weed control efficacy.It is recommended for use in common buckwheat cultivation in the Loess Plateau.展开更多
A population of 180 recombinant inbred lines （RILs） was developed by single seed descended from the cross of high yield Upland cotton （Gossypium hirsutum L.） varieties Zhongmiansuo12 （ZMSI2） and 8891, the two pa...A population of 180 recombinant inbred lines （RILs） was developed by single seed descended from the cross of high yield Upland cotton （Gossypium hirsutum L.） varieties Zhongmiansuo12 （ZMSI2） and 8891, the two parents of Xiangzamian2 （XZM2）. A genetic linkage map consisting of 132 loci and covering 865.20 cM was constructed using the RIL population chiefly with SSR markers. Yield and yield components were investigated for RILs in three environments in China. The purpose of the present research was to analyze the relationship between yield and its components and to map QTL for yield and yield components in cotton. QTL were tagged with data sets from single environment （separate analysis） and a set of data from means of the three environments （joint analysis）. A total of 34 QTL for yield and yield components were independently detected in three environments, whereas fifteen QTL were found in joint analysis. Notably, a stable lint percentage QTL qLP-A10-1 was detected both in joint analysis and in two environments of separate analysis, which might be of special value for marker-assisted selection. The QTL detected in the present study provide new information on improving yield and yield components. Results of path analysis showed that bolls/plant had the largest contribution to lint yield, which is consistent with the mid-parent heterosis value in F1. Accordingly, in cotton breeding, bolls/plant can be considered first and other yield components measured as a whole to implement variety enhancement and hybrid selection of cotton.展开更多
[Objective] The relationship between grain yield and yield components was investigated in .different rice cultivars at the target yield of 10.5-11.25 t/hm2, to provide theoretical basis for cultivation of high-yield r...[Objective] The relationship between grain yield and yield components was investigated in .different rice cultivars at the target yield of 10.5-11.25 t/hm2, to provide theoretical basis for cultivation of high-yield rice. [Method] The yield performance of various super rice and non-super rice cultivars that were cultivated in large area in Sichuan Chengdu was studied under high-yielding cultivation conditions from 2006 to 2008. [Result] The rice yield was closely correlated with the productive panicle number, grain number per panicle, seed setting rate and 1 000-grain weight. The four yield components showed different influences on the yield of different rice culti- vars. By adopting the high yielding cultivation technology （that the seedlings were planted in a triangle shape） at the target yield of 10.5-11.25 t/hm~, we found that the rice yield of super rice cultivars was closely correlated with productive panicle number and 1 000-grain weight, negatively correlated with grain number per panicle, and significantly negatively correlated with seed setting rate; the grain yield of non- super rice cultivars was negatively correlated with grain number per panicle and seed setting rate, and significantly negatively correlated with the productive panicle number and 1 000-grain weight. [Conclusion] The results revealed the relationship between grain yield and yield components in different rice cultivars, which provided references for developing reasonable cultivation measures and thus to improve the yield of super rice in large acreage.展开更多
ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice （Nanjing 44）. MethodThe rice seeds were soaked in 0 （water as a control）, 1, 2, 4 and 6 ...ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice （Nanjing 44）. MethodThe rice seeds were soaked in 0 （water as a control）, 1, 2, 4 and 6 g/L fulvic acid （FA） before sowed. Then, the rice morphological indices, leaf chlorophyll content, photosynthesis parameters, root activity and chlorophyll fluorescence parameters were measured in the following field studies. ResultCompared with the control, the leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance and dry matter weight and some fluorescence parameters such as the maximum photochemical efficiency of photosystem II （PSII） （Fv/Fm）, excitation energy capture efficiency of opened PSII reaction center （Fv’/Fm’） and efficiency of the open reaction centre （ΦPS II） increased by different levels at both jointing stage and heading stage of direct seeding rice, whose seeds were soaked by FA with different concentrations. High FA concentration （4-6 g/L） significantly increased the cultivated rice leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and dry matter weight by 10.32% -22.88% , 5.88% -13.11% , 12.16% -26.84% , 11.43% -88.46% , 10.63% -21.63% , 18.49% -19.68% , respectively, thereby improving the physiological function and light energy transform efficiency of rice at the growth stage. With FA concentration increasing, the yield, effective panicles, grain number per panicle and seed setting rate were increased significantly compared with the control by 17.52%-18.71%, 3.46%-3.85%, 6.30%- 6.51% and 7.82%-8.69% respectively. ConclusionSoaking rice seed with FA could be considered as an effective way to improve the rice competitiveness at early growth stage.展开更多
[Objective] The experiment aimed to study the relation between yield components and yield per plant of double-low hybrid rapeseed and provide reference for breaking yield limitation of rapeseed and culturing new doubl...[Objective] The experiment aimed to study the relation between yield components and yield per plant of double-low hybrid rapeseed and provide reference for breaking yield limitation of rapeseed and culturing new double-low hybrid rapeseed variety. [Method]The yield components and yield per plant of two cross combination of double-low hybrid rapeseed (B02, D04) and Shuza 6 were correlatively analyzed and compared, besides, the path analysis was also carried on to them. [Result] Among B02, D04 and Shuza No.6, effective pod number per plant and seeds per silique, seeds per pod and 1 000-grain weight were all negative correlation. In high yield hybrid, pod number per plant, seeds per pod had more impaction on yield per plant than 1 000-grain weight and the difference was at 0.01 significant level. In the control variety Shuza No.6, the impactions of pod number per plant and seeds per pod on yield per plant were bigger than that of 1 000-grain weight on yield per plant, however, the difference was not significant. [Conclusion] The improvement of effective pod number per plant was an important aim of breeding work of double low rapeseed breeding in Sichuan ecological region.展开更多
[Objective] This study was conducted to improve unit yield of rice in Longyang District and find the relationship between transplanting density and rice yield. [Method] Under the condition of field plot test, effects ...[Objective] This study was conducted to improve unit yield of rice in Longyang District and find the relationship between transplanting density and rice yield. [Method] Under the condition of field plot test, effects of cultivation density on yield and yield components were investigated with japonica rice Longke 16 as a test material. [Result] Under a planting density of 2.7-3.3×10^5 clusters/hm^2, equivalent to a density of seedlings with tillers of 5.4-6.6×10^5/hm^2, the yield reached 11 250-12 000 kg/hm^2. [Conclusion] Longke 16 is a japonica rice variety with good comprehensive characters, and rational dense planting and accurate quantitative cultivation could give full play to its high yield potential.展开更多
[Objective] To understand the application effects of urea ammonium chloride fertilizer on maize production. [Methods] A field plot experiment was conducted to study the effects of urea ammonium chloride of different f...[Objective] To understand the application effects of urea ammonium chloride fertilizer on maize production. [Methods] A field plot experiment was conducted to study the effects of urea ammonium chloride of different fertilization patterns on summer maize yield and yield components. [Results] Urea ammonium chloride had a long fertilizer effect and the same yield-increasing effect with urea, which could im- prove the agronomic traits and economic traits of maize apparently and the applica- tion of urea ammonium chloride with nutrient reduction of 40% （namely just use urea ammonium chloride equaled 60% pure nitrogen）, had the same yield-increasing effect with urea of traditional fertilization patterns, and input-output ratio was high and the economic benefit was remarkable. [Conclusion] To provide scientific theoretical direc- tion for large area popularization and application of urea ammonium chloride.展开更多
A genetic linkage map with 89 SSR marker loci was constructed based on a maize (Zea mays L.) population consisting of 184 F-2 individuals from the cross, Huangzao 4 X Ye 107. The 184 F-3 families were evaluated in the...A genetic linkage map with 89 SSR marker loci was constructed based on a maize (Zea mays L.) population consisting of 184 F-2 individuals from the cross, Huangzao 4 X Ye 107. The 184 F-3 families were evaluated in the field under well-watered and drought-stressed regimes in Shanxi Province of China. The objectives of the study were to identify genetic segments responsible for the expression of anthesis-silking interval (ASI), ear setting and grain yield, and to examine if the quantitative trait loci (QTLs) for ASI or yield components can be used in marker-assisted selection (MAS) to improve grain yield under drought conditions. Results showed that under well-watered and drought-stressed regimes, three and two QTLs involved in the expression of ASI were detected on chromosomes 1, 2 and 3, and 2 and 5, respectively. Under well-watered regime, two QTLs for ear setting were detected on chromosomes 3 and 6, explaining about 19.9% of the phenotypic variance, and displayed additive and partial dominant effects, respectively. Under drought-stressed condition, four QTLs for ear setting were detected on chromosomes 3, 7 and 10, which were responsible for interpreting 60.4% of the phenotypic variance, and showed dominant or partial dominant effects. Under well-watered condition, four QTLs controlling grain yield were identified on chromosomes 3, 6 and 7, while five QTLs were identified under drought stress on chromosomes 1, 2, 4 and 8. The gene action was of additive or partial dominant effects, and each QTL could explain 7.3% to 22.0% of the phenotypic variance, respectively. Under drought conditions, ASI and ear setting percentage were highly correlated with grain yield, which can be used as secondary traits for grain yield selection. Based on linked markers detected and gene action analyzed, an MAS strategy for yield improvement under drought condition could be established, which consists of QTLs contributing to decreased ASI and to increased ear setting and grain yield, respectively.展开更多
Genetic analysis of yield and yield components were carried out on three parental clones of Coffea canephora Pierre and their controlled hybrid progenies. There is a possibility to estimate coffee yield capabilities i...Genetic analysis of yield and yield components were carried out on three parental clones of Coffea canephora Pierre and their controlled hybrid progenies. There is a possibility to estimate coffee yield capabilities in simply via the easier measuring traits of yield components since significant correlation between them were detected. We found that among parental show very few significantly differences of all observed characters and even not found between the overall mean of the descendants and their donor parents, whereas some particular descendants show higher values rather than their donor parent in one or more characters. Increased value between the best parent to the best descendent were detected varies from zero to 102%. This situation suggests the difficulty to find out the optimum yield in a single plant by accumulating all of yield components that actually can increase 143% to 278% from actual to potential yields. In addition, observed characters among population were also actually found highly varies from 159% in out-turn in population B to 28,333% in number of productive branch among population A. Low heritability （h2） that generally found in quantitative traits due to polygenic control was present in our studies in almost all characters observed. Therefore, selection for actual high yielding through conventional breeding will not efficient, and more convincing the power of selection using molecular markers to assist for cumulate additive effects in a single genotypes that resulted of high yielding in the future.展开更多
Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of ...Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of sweet potato. The results showed that plastic filming mulching increased soil temperature. Considering the soil temperature-increasing effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. However, with the deepening of soil layer, the warming effect of plastic film mulching was weakened. Black or white plastic film mulching was conducive to low T/R value, especially in the early growth stage of sweet potato. Plastic film mulching significantly improved the storage root yield of sweet potato. In terms of yield-improving effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. The storage root num- ber per plant showed a downward trend, but the weight of single storage root was increased.展开更多
Proper mineral nutrition of red clover especially on the acid soils is a prerequisite for the realization of maximum potential for seed yield. The field experiment with four cultivars of red clover were established on...Proper mineral nutrition of red clover especially on the acid soils is a prerequisite for the realization of maximum potential for seed yield. The field experiment with four cultivars of red clover were established on soil having a pH （in H2O） of 4.8, in order to in conditions of dense planting （20 cm inter row） analyzes the effect of foliar application of phosphorus and potassium （PK） on yield and yield components （number of stems/m2, number of inflorescences/m2, number of inflorescences/stem, number of flowers/inflorescence, number of seeds/inflorescence and one thousand grain weight）. Regardless of foliar treatment with PK, varieties differed in the number of inflorescences/m2, number of flowers/inflorescence, number of seeds/inflorescence and seed yield. Foliar application of PK in the phase of intensive growth of red clover had a positive impact on number of stem/m2, number of inflorescences/m2 and seed yield in all varieties, as well as on the number of flowers/inflorescence, number of seeds/inflorescence in cultivar Viola.展开更多
The canopy temperature of rice at the flowering stage and the soil water content were investigated under different soil water treatments （the soil water contents were 24%, 55%, 90% and 175% at the flowering stage）. ...The canopy temperature of rice at the flowering stage and the soil water content were investigated under different soil water treatments （the soil water contents were 24%, 55%, 90% and 175% at the flowering stage）. The canopy temperature was lower than air temperature, and the soil water content significantly influenced the canopy temperature. The lower the soil water content, the higher the canopy temperature, the less the accumulative absolute value of canopy-air temperature difference. Moreover, the maximum difference between treatments and CK in the accumulative absolute value of canopy-air temperature difference appeared at 13：00 μm. in a day, thus, it could be considered as a suitable measuring time. Under the lowest water content treatment, the peak flowering occurred in the first three days （about 70% of panicles flowered）, resulting in shortened and lightened panicle of rice. As to the CK and the high water content treatments, the peak flowering appeared in the middle of flowering duration, with longer panicle length and higher panicle weight. Results indicated the lower the soil water content, the less the filled grain number and grain yield.展开更多
[Objective] The aim was to research relationship of meteorological factors with rapeseed yield and yield components. [Method] A field test was carried out, with meteorological information collected from local Meteorol...[Objective] The aim was to research relationship of meteorological factors with rapeseed yield and yield components. [Method] A field test was carried out, with meteorological information collected from local Meteorological Administration. The data were then through statistical work and regression analysis was made on correlation of meteorological factors with yield and yield components supported by DPS. [Result] The number of pod per plant is closely related to meteorological fac- tors in seedling stage. Specifically, the number is of positive correlation with precipi- tation in seedling stage and of negative correlation with average temperature and sunshine hour. The number of grain per pod is of positive correlation with precipita- tion in seedling stage and negative correlation with temperature in seedling stage and sunshine hour in anthesis. Thousand-seed weight is of positive correlation with sunshine hour in seedling stage and negative correlation with precipitation in seedling stage. [Conclusion] Moisture of soils should be guaranteed by surface cov- erage in order to promote seedling growth, maintain ventilation in fields and reduce effects of rainfall on rapeseed flowering.展开更多
The objective of this study was to determine the relationship between seed yield and other important agronomic traits of early-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson＇s corre...The objective of this study was to determine the relationship between seed yield and other important agronomic traits of early-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson＇s correlation coefficient as well as to estimate direct and indirect effects of specific yield component traits on seed yield via path analysis. Nineteen rapeseed genotypes were grown at ten environments in South China during 2008-2009 and 12 characters were evaluated. Analysis of variance showed that environment had a significant impact on all characters. For most characters the genotype by environment interaction was weak and not statistically significant. Simple correlation analysis indicated that the number of primary branches （PB）, number of pods on the main raceme （PR）, and number of seeds per pod made significant contributions to seed yield per plant （SYP）, while 1 000-seed weight was negatively correlated with SYP （r=-0.485, P0.05）. Furthermore, number of pods per plant （PP）, PB, and PR had the greatest direct effects on SYP. In addition, PP and PB were the best indicators to predict seed yield in stepwise regression analysis. Finally, yield component differences between early- and medium-maturity varieties were compared; this showed that to improve the seed yield of early varieties, more emphasis should be given to increase PP, PB, and PR, and reduce plant height and shortening of growth duration in breeding practice.展开更多
[Objective]The aim was to study on characteristics of retoon rice yield components,and relationship of the characteristics with born bud rate and root ac-tivity of retoon rice before harvesting.[Method]Eighteen mid-se...[Objective]The aim was to study on characteristics of retoon rice yield components,and relationship of the characteristics with born bud rate and root ac-tivity of retoon rice before harvesting.[Method]Eighteen mid-season hybrid rice va-rieties approved recently were taken as materials in high-yield cultivation conditions.Characteristics of retoon rice yield components were analyzed,and relationship of yield components characteristics with the rate of bud emergence and root activity of retoon rice before harvesting was explored,based on related data.[Result]Highly-yielding retoon rice is characterized by high effective ear number(Xl)and high set-ting percentage(X4);the number of germinated shoots the 5^*d after first-batch rice was cut is a key factor for retoon rice yield and was of positive correlation with re-toon rice seedlings and effective ears,with correlation coefficients at 0.80^**and 0.76^**.In addition,bleeding sap was of positive correlation with grain number and setting percentage of retoon rice and correlation coefficients were 0.50^*and 0.48^**,and of positive correlation with average panicle weight,with correlation coefficient at 0.63.[Conclusion]It is an effective way for the rate of bud emergence and root activity at lar ecological zones.mproving retoon rice yield to increase harvesting in the test sites and simi lar ecological zones.展开更多
Resynthesized rapeseeds obtained by crossing the diploid parents Brassica rapa and Brassica oleracea have significant potential in hybrid breeding because of their higher genetic basis compared with Brassica napus cul...Resynthesized rapeseeds obtained by crossing the diploid parents Brassica rapa and Brassica oleracea have significant potential in hybrid breeding because of their higher genetic basis compared with Brassica napus cultivars. In this study, an 8 × 8 complete diallel experiment using four B. napus cultivars （BN） and four resynthesized rapeseed lines （RS） as parents was designed to study heterosis and genetic inheritance for yield components. The results showed that heterosis for yield per plant, the number of pods per plant and number of seeds per pod were high, with means 32.77, 24.49 and 15.71%, respectively. Diallel analysis showed that both additive and dominant effects were significant for yield and yield components. All traits, except for 1 000-seed weight, were significant for bl mean squares and exhibited directional dominance. Dominant genes had positive effects on yield per plant, pods per plant and 1000-seed weight, and negative effects on seeds per pod （r=-0.86, -0.62, -0.41, and 0.47, respectively）. Narrow-sense heritability for yield per plant, pods per plant, and 1 000-seed weight and seeds per pod were 66, 31, 46 and 78% for the four traits, respectively. The Fl hybrids showed considerable yields compared to B. napus cultivars when B. napus cultivars and resynthesized rapeseeds were used as parents （NR hybrids）, with many more pods per plant and lower seeds per pod compared with the rapeseed cultivars, indicating that the resynthesized rapeseed may be applicable in current hybrid breeding programs.展开更多
Field experiments were conducted to assess the impact of various organic sources, inorganicnitrogen （N） and the different combinations of inorganic N （urea） ＋ organic source on the yieldcomponents （YC） and grai...Field experiments were conducted to assess the impact of various organic sources, inorganicnitrogen （N） and the different combinations of inorganic N （urea） ＋ organic source on the yieldcomponents （YC） and grain yield （GY） of hybrid rice （Oryza sativa L., Pukhraj） under rice-wheat system.The experiments were conducted at Batkhela （Malakand）, Northwestern Pakistan, in 2011 and 2012.Our results revealed that YC and GY ranked first for the hybrid rice when applied with sole inorganic N（urea）, followed by the application of N in mixture （urea ＋ organic sources）, while the control plots （no Napplied） ranked in the bottom. Among the six organic sources （three animal manures： poultry, sheepand cattle; three crop residues： onion, berseem and wheat）, application of N in the form of poultrymanure was superior in terms of higher YC and GY. When applying 120 kg/hm2 N source, 75% N fromurea ＋ 25% N from organic source resulted in higher YC and GY in 2011, while applying 50% N fromurea ＋ 50% N from organic sources caused higher YC and GY in 2012. Therefore, the combinedapplication of N sources in the form of urea ＋ organic source can produce good performances in termsof higher YC and GY of rice under rice-wheat cropping system.展开更多
The tea crop provides income and employment to rural populations in many countries. In Kenya, tea, which is the leading export commodity crop, is grown in highlands east and west of the Rift Valley at altitudes rangin...The tea crop provides income and employment to rural populations in many countries. In Kenya, tea, which is the leading export commodity crop, is grown in highlands east and west of the Rift Valley at altitudes ranging from 1300 m to 2700 m above mean sea level. Variable responses of tea genotypes to different environments have been demonstrated. This affects the growth, productivity, and quality of tea. However, most tea husbandry practices are uniform across tea growing regions leading to variations in yields and quality in the different environments. Understanding causes of variations in tea growth parameters and yields to varying environments is vital to optimizing husbandry practices for maximization of productivity. The responses in growth and yield parameters of clonal tea to locations of production and their contribution to yields were compared. A genotype × environment trial was conducted in three sites (Kangaita, Timbilil and Kipkebe). At each site, a trial comprising 20 cultivars was laid in a randomized complete design replicated 3 times. Yields, yield components and climatic data were collected then subjected to analysis of variance and regression analysis. There were significant (p ≤ 0.05) yield variations between clones and locations. Yields ranged from 5162 kg mt/ha on clone TRFK 303/577 at Kipkebe to 935 kg mt/ha/year on clone TRFK 7/3 in Kangaita, surpassing the maximum variation possible postulated in earlier studies. The responses of the tea yield components to weather parameters varied with genotypes and environments. Shoot growth rates in Timbilil (r = 0.476)) and shoot density (Kangaita (r = 0.652) significantly (p ≤ 0.05)) correlated with yields. Yield components and weather parameters contribution to the total yield also varied with locations. The variations demonstrated that not all yield components can be used universally as yield indicators for clonal selection in different locations. For optimal production, selected tea clones should therefore be tested before adoption for commercial planting in other locations.展开更多
文摘Context:In irrigated agriculture,the salt stress is a major problem due to accumulation of salt from the irrigation water in the soil layers.Objectives:The aim of this study is to determinate the effect of salinity on some agromorphological traits and seed nutritional quality of three sesames(Sesamum indicum L.)varieties.Methodology:This is how four solutions of different NaCl concentrations from 0,60,120 to 240 mM were used to water sesame plants at the five-leaves stage and this for two months in completely randomized device with four repetitions.Results:The results show a negative effect of the salinity growth and yield parameters,mineral elements,ascorbic acid(to 21.4% in White cultivar,28% in Brown and 24.2% in Black cultivar from 0 to 240 mM NaCl),oil(to 22.6%in White cultivar,32% in Brown and 25.5% in Black cultivar from 0 to 240 mM NaCl)and accumulation of Na(Sodium)content(to 11.8% in White cultivar,15.3% in Brown and 12.2% in Black cultivar from 0 to 240 mM NaCl),osmolytes as proteins(to 14.5% in White cultivar,11.5% in Brown and 9.6%in Black cultivar from 0 to 240 mM NaCl)and antioxydants components.Varieties White and Brown were less affected by salinity.Conclusion:White variety exhibited higher adaptive potential under salinity stress when compared to Brown variety(rich in fiber)and closely followed by Black variety.Thus White variety could be recommended for consumer oil,minerals and proteins.As for Black variety,it could be used,as glucid and antioxydants additives in food.
基金supported by the National Natural Science Foundation of China(32161143006,32171997)the Earmarked Fund for CARS-13,and the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(No.CAAS-ASTIP-2021-OCRI).
文摘Bacterial wilt(BW)caused by Ralstonia solanacearum is a wide-spread and serious disease in peanut.To date,this soilborne disease could only be effectively controlled by planting resistant peanut cultivars.However,the relatively lower yield potential of the available BW-resistant peanut cultivars is a key reason restricting productivity in most epidemic regions naturally infested with the pathogen.Even small pods or seeds and low number per plant has been regarded as the key factor for the low yield potential both in BW-resistant peanut germplasm lines and available released cultivars,whether the resistance is closely linked with key yield components remains unclear.In this study,the relationship between pod weight and BW resistance was analyzed by using a recombinant inbred lines(RIL)population derived from a crossing combination between a high yielding cultivar Xuhua 13 and a BW-resistant cultivar Zhonghua 6.From the experiments,it was found that the BW resistance was not significantly correlated with pod number per plant(PNP),hundred pod weight(HPW)and pod weight per plant(PWP)in the RIL population.Based on linkage analysis,the quantitative trait locus(QTL)s related to PNP were identified on A06,A07,A08 and B03.The QTLs for HPW were detected on A05 and A07,and the QTLs for PWP were on A06,A07 and B03.However,the QTL for BW resistance identified on B02.These results indicated that the BW resistance and the pod number per plant as well as pod weight were inherited independently.Two recombined lines(QT0944 and QT1028)with high level BW resistance and large pods(hundred pod weight over 185g)were identified from the RILs,and they possessed the favored alleles of identified QTLs from both parents,which could be used in peanut breeding for high yield and high level disease resistance.
基金supported by the Science and Technology Key Research&Development Project of Shaanxi Province(2022NY-178)the Technical System of Minor Cereals Industry in Shaanxi Province(NYKJ-2022-YL(XN)28)the Special Fund for Seed Industrial Development in Shaanxi Province(K3031223130).
文摘Herbicide safeners alleviate herbicide toxicity while preserving weed-control efficacy in common buckwheat.A three-year field experiment was performed to measure the effects of quizalofop-P-ethyl(QPE)alone or in combination with gibberellin or brassinolide on soil enzyme activity and yield components in common buckwheat.The herbicide-brassinolide application yielded the greatest increases in soil enzyme activity and yield components without sacrificing weed control efficacy.It is recommended for use in common buckwheat cultivation in the Loess Plateau.
基金This work was supported by the National Science Foundation for Outstanding Youth Scholars (No. 30025029), Chinese National Programs for High Technology Research and Development (No. 2002AA207006), the Teaching and Research Award Program for Outstanding Young Teachers in Higher Education Institutions, and Program for Changjiang Scholars and Innovative Research Team in University of MOE, China.
文摘A population of 180 recombinant inbred lines （RILs） was developed by single seed descended from the cross of high yield Upland cotton （Gossypium hirsutum L.） varieties Zhongmiansuo12 （ZMSI2） and 8891, the two parents of Xiangzamian2 （XZM2）. A genetic linkage map consisting of 132 loci and covering 865.20 cM was constructed using the RIL population chiefly with SSR markers. Yield and yield components were investigated for RILs in three environments in China. The purpose of the present research was to analyze the relationship between yield and its components and to map QTL for yield and yield components in cotton. QTL were tagged with data sets from single environment （separate analysis） and a set of data from means of the three environments （joint analysis）. A total of 34 QTL for yield and yield components were independently detected in three environments, whereas fifteen QTL were found in joint analysis. Notably, a stable lint percentage QTL qLP-A10-1 was detected both in joint analysis and in two environments of separate analysis, which might be of special value for marker-assisted selection. The QTL detected in the present study provide new information on improving yield and yield components. Results of path analysis showed that bolls/plant had the largest contribution to lint yield, which is consistent with the mid-parent heterosis value in F1. Accordingly, in cotton breeding, bolls/plant can be considered first and other yield components measured as a whole to implement variety enhancement and hybrid selection of cotton.
基金Supported by the National Key Technology Research and Development Program of China during the 11thFive-Year Plan Period (2004BA520A05)Technology Research and Development Program of Sichuan Province (2008FZ0036)Key Technology Research and Development Program of Deyang City (2007ND028)~~
文摘[Objective] The relationship between grain yield and yield components was investigated in .different rice cultivars at the target yield of 10.5-11.25 t/hm2, to provide theoretical basis for cultivation of high-yield rice. [Method] The yield performance of various super rice and non-super rice cultivars that were cultivated in large area in Sichuan Chengdu was studied under high-yielding cultivation conditions from 2006 to 2008. [Result] The rice yield was closely correlated with the productive panicle number, grain number per panicle, seed setting rate and 1 000-grain weight. The four yield components showed different influences on the yield of different rice culti- vars. By adopting the high yielding cultivation technology （that the seedlings were planted in a triangle shape） at the target yield of 10.5-11.25 t/hm~, we found that the rice yield of super rice cultivars was closely correlated with productive panicle number and 1 000-grain weight, negatively correlated with grain number per panicle, and significantly negatively correlated with seed setting rate; the grain yield of non- super rice cultivars was negatively correlated with grain number per panicle and seed setting rate, and significantly negatively correlated with the productive panicle number and 1 000-grain weight. [Conclusion] The results revealed the relationship between grain yield and yield components in different rice cultivars, which provided references for developing reasonable cultivation measures and thus to improve the yield of super rice in large acreage.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201303022)National Key Technology Research and Development Program during the 12th Five-Year Plan Period(2012BAD19B02)~~
文摘ObjectiveThis study aimed to investigate the effect of fulvic acid on the growth and yield components of direct seeding rice （Nanjing 44）. MethodThe rice seeds were soaked in 0 （water as a control）, 1, 2, 4 and 6 g/L fulvic acid （FA） before sowed. Then, the rice morphological indices, leaf chlorophyll content, photosynthesis parameters, root activity and chlorophyll fluorescence parameters were measured in the following field studies. ResultCompared with the control, the leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance and dry matter weight and some fluorescence parameters such as the maximum photochemical efficiency of photosystem II （PSII） （Fv/Fm）, excitation energy capture efficiency of opened PSII reaction center （Fv’/Fm’） and efficiency of the open reaction centre （ΦPS II） increased by different levels at both jointing stage and heading stage of direct seeding rice, whose seeds were soaked by FA with different concentrations. High FA concentration （4-6 g/L） significantly increased the cultivated rice leaf area index, chlorophyll content, net photosynthetic rate, stomatal conductance, transpiration rate and dry matter weight by 10.32% -22.88% , 5.88% -13.11% , 12.16% -26.84% , 11.43% -88.46% , 10.63% -21.63% , 18.49% -19.68% , respectively, thereby improving the physiological function and light energy transform efficiency of rice at the growth stage. With FA concentration increasing, the yield, effective panicles, grain number per panicle and seed setting rate were increased significantly compared with the control by 17.52%-18.71%, 3.46%-3.85%, 6.30%- 6.51% and 7.82%-8.69% respectively. ConclusionSoaking rice seed with FA could be considered as an effective way to improve the rice competitiveness at early growth stage.
基金Supported by Key Germplasm Project of Sichuan Province during the Eleventh Five-year Plan(2006YZGG-23)~~
文摘[Objective] The experiment aimed to study the relation between yield components and yield per plant of double-low hybrid rapeseed and provide reference for breaking yield limitation of rapeseed and culturing new double-low hybrid rapeseed variety. [Method]The yield components and yield per plant of two cross combination of double-low hybrid rapeseed (B02, D04) and Shuza 6 were correlatively analyzed and compared, besides, the path analysis was also carried on to them. [Result] Among B02, D04 and Shuza No.6, effective pod number per plant and seeds per silique, seeds per pod and 1 000-grain weight were all negative correlation. In high yield hybrid, pod number per plant, seeds per pod had more impaction on yield per plant than 1 000-grain weight and the difference was at 0.01 significant level. In the control variety Shuza No.6, the impactions of pod number per plant and seeds per pod on yield per plant were bigger than that of 1 000-grain weight on yield per plant, however, the difference was not significant. [Conclusion] The improvement of effective pod number per plant was an important aim of breeding work of double low rapeseed breeding in Sichuan ecological region.
基金Supported by Longyang District Regional Extension Station of Agricultural Research System for Rice Industry in Yunnan Province[YNKZ(2009)53,YCNZ(2009)171]~~
文摘[Objective] This study was conducted to improve unit yield of rice in Longyang District and find the relationship between transplanting density and rice yield. [Method] Under the condition of field plot test, effects of cultivation density on yield and yield components were investigated with japonica rice Longke 16 as a test material. [Result] Under a planting density of 2.7-3.3×10^5 clusters/hm^2, equivalent to a density of seedlings with tillers of 5.4-6.6×10^5/hm^2, the yield reached 11 250-12 000 kg/hm^2. [Conclusion] Longke 16 is a japonica rice variety with good comprehensive characters, and rational dense planting and accurate quantitative cultivation could give full play to its high yield potential.
基金Supported by Construction Project of Maize Industry Technology System of Modern Agriculture in Yunnan Province(Yunnong(ke)2009-53Yunnongcai(2009-171))~~
文摘[Objective] To understand the application effects of urea ammonium chloride fertilizer on maize production. [Methods] A field plot experiment was conducted to study the effects of urea ammonium chloride of different fertilization patterns on summer maize yield and yield components. [Results] Urea ammonium chloride had a long fertilizer effect and the same yield-increasing effect with urea, which could im- prove the agronomic traits and economic traits of maize apparently and the applica- tion of urea ammonium chloride with nutrient reduction of 40% （namely just use urea ammonium chloride equaled 60% pure nitrogen）, had the same yield-increasing effect with urea of traditional fertilization patterns, and input-output ratio was high and the economic benefit was remarkable. [Conclusion] To provide scientific theoretical direc- tion for large area popularization and application of urea ammonium chloride.
文摘A genetic linkage map with 89 SSR marker loci was constructed based on a maize (Zea mays L.) population consisting of 184 F-2 individuals from the cross, Huangzao 4 X Ye 107. The 184 F-3 families were evaluated in the field under well-watered and drought-stressed regimes in Shanxi Province of China. The objectives of the study were to identify genetic segments responsible for the expression of anthesis-silking interval (ASI), ear setting and grain yield, and to examine if the quantitative trait loci (QTLs) for ASI or yield components can be used in marker-assisted selection (MAS) to improve grain yield under drought conditions. Results showed that under well-watered and drought-stressed regimes, three and two QTLs involved in the expression of ASI were detected on chromosomes 1, 2 and 3, and 2 and 5, respectively. Under well-watered regime, two QTLs for ear setting were detected on chromosomes 3 and 6, explaining about 19.9% of the phenotypic variance, and displayed additive and partial dominant effects, respectively. Under drought-stressed condition, four QTLs for ear setting were detected on chromosomes 3, 7 and 10, which were responsible for interpreting 60.4% of the phenotypic variance, and showed dominant or partial dominant effects. Under well-watered condition, four QTLs controlling grain yield were identified on chromosomes 3, 6 and 7, while five QTLs were identified under drought stress on chromosomes 1, 2, 4 and 8. The gene action was of additive or partial dominant effects, and each QTL could explain 7.3% to 22.0% of the phenotypic variance, respectively. Under drought conditions, ASI and ear setting percentage were highly correlated with grain yield, which can be used as secondary traits for grain yield selection. Based on linked markers detected and gene action analyzed, an MAS strategy for yield improvement under drought condition could be established, which consists of QTLs contributing to decreased ASI and to increased ear setting and grain yield, respectively.
文摘Genetic analysis of yield and yield components were carried out on three parental clones of Coffea canephora Pierre and their controlled hybrid progenies. There is a possibility to estimate coffee yield capabilities in simply via the easier measuring traits of yield components since significant correlation between them were detected. We found that among parental show very few significantly differences of all observed characters and even not found between the overall mean of the descendants and their donor parents, whereas some particular descendants show higher values rather than their donor parent in one or more characters. Increased value between the best parent to the best descendent were detected varies from zero to 102%. This situation suggests the difficulty to find out the optimum yield in a single plant by accumulating all of yield components that actually can increase 143% to 278% from actual to potential yields. In addition, observed characters among population were also actually found highly varies from 159% in out-turn in population B to 28,333% in number of productive branch among population A. Low heritability （h2） that generally found in quantitative traits due to polygenic control was present in our studies in almost all characters observed. Therefore, selection for actual high yielding through conventional breeding will not efficient, and more convincing the power of selection using molecular markers to assist for cumulate additive effects in a single genotypes that resulted of high yielding in the future.
基金Supported by National Sweet Potato Industrial Technology System(CARS-11-C-16)~~
文摘Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of sweet potato. The results showed that plastic filming mulching increased soil temperature. Considering the soil temperature-increasing effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. However, with the deepening of soil layer, the warming effect of plastic film mulching was weakened. Black or white plastic film mulching was conducive to low T/R value, especially in the early growth stage of sweet potato. Plastic film mulching significantly improved the storage root yield of sweet potato. In terms of yield-improving effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. The storage root num- ber per plant showed a downward trend, but the weight of single storage root was increased.
文摘Proper mineral nutrition of red clover especially on the acid soils is a prerequisite for the realization of maximum potential for seed yield. The field experiment with four cultivars of red clover were established on soil having a pH （in H2O） of 4.8, in order to in conditions of dense planting （20 cm inter row） analyzes the effect of foliar application of phosphorus and potassium （PK） on yield and yield components （number of stems/m2, number of inflorescences/m2, number of inflorescences/stem, number of flowers/inflorescence, number of seeds/inflorescence and one thousand grain weight）. Regardless of foliar treatment with PK, varieties differed in the number of inflorescences/m2, number of flowers/inflorescence, number of seeds/inflorescence and seed yield. Foliar application of PK in the phase of intensive growth of red clover had a positive impact on number of stem/m2, number of inflorescences/m2 and seed yield in all varieties, as well as on the number of flowers/inflorescence, number of seeds/inflorescence in cultivar Viola.
基金This paper was translated from its Chinese version in Chinese Journal of Rice Science.
文摘The canopy temperature of rice at the flowering stage and the soil water content were investigated under different soil water treatments （the soil water contents were 24%, 55%, 90% and 175% at the flowering stage）. The canopy temperature was lower than air temperature, and the soil water content significantly influenced the canopy temperature. The lower the soil water content, the higher the canopy temperature, the less the accumulative absolute value of canopy-air temperature difference. Moreover, the maximum difference between treatments and CK in the accumulative absolute value of canopy-air temperature difference appeared at 13：00 μm. in a day, thus, it could be considered as a suitable measuring time. Under the lowest water content treatment, the peak flowering occurred in the first three days （about 70% of panicles flowered）, resulting in shortened and lightened panicle of rice. As to the CK and the high water content treatments, the peak flowering appeared in the middle of flowering duration, with longer panicle length and higher panicle weight. Results indicated the lower the soil water content, the less the filled grain number and grain yield.
基金Supported by National Natural Science Foundation of China(31360346)Yunnan Modern Agricultural Rapeseed-industry Technology System~~
文摘[Objective] The aim was to research relationship of meteorological factors with rapeseed yield and yield components. [Method] A field test was carried out, with meteorological information collected from local Meteorological Administration. The data were then through statistical work and regression analysis was made on correlation of meteorological factors with yield and yield components supported by DPS. [Result] The number of pod per plant is closely related to meteorological fac- tors in seedling stage. Specifically, the number is of positive correlation with precipi- tation in seedling stage and of negative correlation with average temperature and sunshine hour. The number of grain per pod is of positive correlation with precipita- tion in seedling stage and negative correlation with temperature in seedling stage and sunshine hour in anthesis. Thousand-seed weight is of positive correlation with sunshine hour in seedling stage and negative correlation with precipitation in seedling stage. [Conclusion] Moisture of soils should be guaranteed by surface cov- erage in order to promote seedling growth, maintain ventilation in fields and reduce effects of rainfall on rapeseed flowering.
基金supported by the funds from the National Key Technologies R&D Program (2009BA DA8 B01 and 2010BAD01B09)the National High-Tech R&D Program (863 Program) of China (2011AA10A104)
文摘The objective of this study was to determine the relationship between seed yield and other important agronomic traits of early-maturing rapeseed as a rotation crop in a double-cropping rice area using Pearson＇s correlation coefficient as well as to estimate direct and indirect effects of specific yield component traits on seed yield via path analysis. Nineteen rapeseed genotypes were grown at ten environments in South China during 2008-2009 and 12 characters were evaluated. Analysis of variance showed that environment had a significant impact on all characters. For most characters the genotype by environment interaction was weak and not statistically significant. Simple correlation analysis indicated that the number of primary branches （PB）, number of pods on the main raceme （PR）, and number of seeds per pod made significant contributions to seed yield per plant （SYP）, while 1 000-seed weight was negatively correlated with SYP （r=-0.485, P0.05）. Furthermore, number of pods per plant （PP）, PB, and PR had the greatest direct effects on SYP. In addition, PP and PB were the best indicators to predict seed yield in stepwise regression analysis. Finally, yield component differences between early- and medium-maturity varieties were compared; this showed that to improve the seed yield of early varieties, more emphasis should be given to increase PP, PB, and PR, and reduce plant height and shortening of growth duration in breeding practice.
文摘[Objective]The aim was to study on characteristics of retoon rice yield components,and relationship of the characteristics with born bud rate and root ac-tivity of retoon rice before harvesting.[Method]Eighteen mid-season hybrid rice va-rieties approved recently were taken as materials in high-yield cultivation conditions.Characteristics of retoon rice yield components were analyzed,and relationship of yield components characteristics with the rate of bud emergence and root activity of retoon rice before harvesting was explored,based on related data.[Result]Highly-yielding retoon rice is characterized by high effective ear number(Xl)and high set-ting percentage(X4);the number of germinated shoots the 5^*d after first-batch rice was cut is a key factor for retoon rice yield and was of positive correlation with re-toon rice seedlings and effective ears,with correlation coefficients at 0.80^**and 0.76^**.In addition,bleeding sap was of positive correlation with grain number and setting percentage of retoon rice and correlation coefficients were 0.50^*and 0.48^**,and of positive correlation with average panicle weight,with correlation coefficient at 0.63.[Conclusion]It is an effective way for the rate of bud emergence and root activity at lar ecological zones.mproving retoon rice yield to increase harvesting in the test sites and simi lar ecological zones.
基金supported by the National Natural Science Foundation of China (30471009)
文摘Resynthesized rapeseeds obtained by crossing the diploid parents Brassica rapa and Brassica oleracea have significant potential in hybrid breeding because of their higher genetic basis compared with Brassica napus cultivars. In this study, an 8 × 8 complete diallel experiment using four B. napus cultivars （BN） and four resynthesized rapeseed lines （RS） as parents was designed to study heterosis and genetic inheritance for yield components. The results showed that heterosis for yield per plant, the number of pods per plant and number of seeds per pod were high, with means 32.77, 24.49 and 15.71%, respectively. Diallel analysis showed that both additive and dominant effects were significant for yield and yield components. All traits, except for 1 000-seed weight, were significant for bl mean squares and exhibited directional dominance. Dominant genes had positive effects on yield per plant, pods per plant and 1000-seed weight, and negative effects on seeds per pod （r=-0.86, -0.62, -0.41, and 0.47, respectively）. Narrow-sense heritability for yield per plant, pods per plant, and 1 000-seed weight and seeds per pod were 66, 31, 46 and 78% for the four traits, respectively. The Fl hybrids showed considerable yields compared to B. napus cultivars when B. napus cultivars and resynthesized rapeseeds were used as parents （NR hybrids）, with many more pods per plant and lower seeds per pod compared with the rapeseed cultivars, indicating that the resynthesized rapeseed may be applicable in current hybrid breeding programs.
基金supported by the Higher Education Commission(HEC)of Pakistan,Islamabad
文摘Field experiments were conducted to assess the impact of various organic sources, inorganicnitrogen （N） and the different combinations of inorganic N （urea） ＋ organic source on the yieldcomponents （YC） and grain yield （GY） of hybrid rice （Oryza sativa L., Pukhraj） under rice-wheat system.The experiments were conducted at Batkhela （Malakand）, Northwestern Pakistan, in 2011 and 2012.Our results revealed that YC and GY ranked first for the hybrid rice when applied with sole inorganic N（urea）, followed by the application of N in mixture （urea ＋ organic sources）, while the control plots （no Napplied） ranked in the bottom. Among the six organic sources （three animal manures： poultry, sheepand cattle; three crop residues： onion, berseem and wheat）, application of N in the form of poultrymanure was superior in terms of higher YC and GY. When applying 120 kg/hm2 N source, 75% N fromurea ＋ 25% N from organic source resulted in higher YC and GY in 2011, while applying 50% N fromurea ＋ 50% N from organic sources caused higher YC and GY in 2012. Therefore, the combinedapplication of N sources in the form of urea ＋ organic source can produce good performances in termsof higher YC and GY of rice under rice-wheat cropping system.
文摘The tea crop provides income and employment to rural populations in many countries. In Kenya, tea, which is the leading export commodity crop, is grown in highlands east and west of the Rift Valley at altitudes ranging from 1300 m to 2700 m above mean sea level. Variable responses of tea genotypes to different environments have been demonstrated. This affects the growth, productivity, and quality of tea. However, most tea husbandry practices are uniform across tea growing regions leading to variations in yields and quality in the different environments. Understanding causes of variations in tea growth parameters and yields to varying environments is vital to optimizing husbandry practices for maximization of productivity. The responses in growth and yield parameters of clonal tea to locations of production and their contribution to yields were compared. A genotype × environment trial was conducted in three sites (Kangaita, Timbilil and Kipkebe). At each site, a trial comprising 20 cultivars was laid in a randomized complete design replicated 3 times. Yields, yield components and climatic data were collected then subjected to analysis of variance and regression analysis. There were significant (p ≤ 0.05) yield variations between clones and locations. Yields ranged from 5162 kg mt/ha on clone TRFK 303/577 at Kipkebe to 935 kg mt/ha/year on clone TRFK 7/3 in Kangaita, surpassing the maximum variation possible postulated in earlier studies. The responses of the tea yield components to weather parameters varied with genotypes and environments. Shoot growth rates in Timbilil (r = 0.476)) and shoot density (Kangaita (r = 0.652) significantly (p ≤ 0.05)) correlated with yields. Yield components and weather parameters contribution to the total yield also varied with locations. The variations demonstrated that not all yield components can be used universally as yield indicators for clonal selection in different locations. For optimal production, selected tea clones should therefore be tested before adoption for commercial planting in other locations.
