A field trial was conducted to investigate the changes of endogenous hormone concentration (EHC) during formation and thickening of tuberous roots in sweet potato (Ipomoea batatas L.) of different genotypes: Xush...A field trial was conducted to investigate the changes of endogenous hormone concentration (EHC) during formation and thickening of tuberous roots in sweet potato (Ipomoea batatas L.) of different genotypes: Xushu 18, Minamiyutaka, and L trifida-K123. The results of this study suggested that the concentrations of zeatin riboside (ZR), dihydro-zeatin riboside (DHZR), abscisic acid (ABA), indole-3-acetic acid (IAA), and isopentenyl-adenine (IPA) of Xushu 18 and Minamiyutaka were significantly higher than those of I. trifida-K123. Dry tuberous root yields were positively correlated with the concentration of ABA, ZR, and DHZR at 1 or 5% significant level, but were not obviously correlated with the concentrations of IAA, IPA, and GA4. The concentrations of ABA, ZR and DHZR played very important roles in the tuberous root formation and thickening in sweet potato. The concentrations of ZR, DHZR, ABA, and IAA in the upper or inner portion of tuberous roots were significantly higher than those toward the end of the root or its outer portion. Meanwhile, EHC of large-sized tuberous roots were significantly higher than those of medium- or small-sized tubers during the early thickening period. In the rapid thickening period of tuberous roots, EHC of medium-sized tubers were the highest, However, at the late-thickening period, EHC of small-sized tubers ranked the highest.展开更多
The IAA, GA3, iPA, ZR and ABA contents in sweet potato leaves under drought conditions were determined by the method of ELISA, and the relationship between these endogenous hormones and drought resistance of different...The IAA, GA3, iPA, ZR and ABA contents in sweet potato leaves under drought conditions were determined by the method of ELISA, and the relationship between these endogenous hormones and drought resistance of different sweet potato varieties were studied. The results showed the IAA, GA3, iPA and ZR contents in sweet potato leaves decreased, but ABA contents increased obviously. The stronger the drought resistance of the variety was, the more IAA, GA3, iPA and ZR contents decreased and the less ABA contents increased. Their relative contents correlated significantly negatively(r were -0.9070, -0.9493, -0.9509, -0.8674 and -0.9117 respectively)to drought-resistability.展开更多
Red and blue light illumination has been reported to significantly affect plantlet growth.Potato is an important food and feed crop in the world and potato plantlet cultured in vitro plays an important role in potato ...Red and blue light illumination has been reported to significantly affect plantlet growth.Potato is an important food and feed crop in the world and potato plantlet cultured in vitro plays an important role in potato production.However,few studies have documented the effects of red and blue light on the growth of potato plantlets revealed at the transcriptome level.The objective of this study was to determine the growth and physiological responses of potato plantlets cultured in vitro under monochromatic red(RR),monochromatic blue(BB)as well as combined red and blue(RB)LEDs using the RNA-Seq technique.In total,3150 and 814 differentially expressed genes(DEGs)were detected in potato plantlets under RR and BB,respectively,compared to RB(used as control).Compared to the control,the DEGs enriched in"photosynthesis"and"photosynthesis-antenna proteins"metabolic pathways were up-regulated and down-regulated by BB and RR,respectively,which might be responsible for the increases and decreases of maximum quantum yield(F_(v)/F_(m)),photochemical quantum yield(φ_(PSII)),photochemical quenching(q_(P))and electron transfer rate(ETR)in BB and RR,respectively.Potato plantlets exhibited dwarfed stems and extended leaves under BB,whereas elongated stems and small leaves were induced under RR.These dramatically altered plantlet phenotypes were associated with variable levels of endogenous plant hormones gibberellin(GAs),indoleacetic acid(IAA)and cytokinins(CKs),as assessed in stems and leaves of potato plantlets.In addition,monochromatic red and blue LEDs trigged the opposite expression profiles of DEGs identified in the"plant hormone signal transduction"metabolic pathway,which were closely related to the endogenous plant hormone levels in potato plantlets.Our results provide insights into the responses of potato plantlets cultured in vitro to red and blue LEDs at the transcriptomic level and may contribute to improvements in the micro-propagation of potato plantlets cultured in vitro from the light spectrum aspect.展开更多
Early tuberization,a short period from stolon occurrence to tuber formation,is one of the major characteristics of a good early-maturing potato cultivar,while the regulatory mechanism of tuberization time(TT)is still ...Early tuberization,a short period from stolon occurrence to tuber formation,is one of the major characteristics of a good early-maturing potato cultivar,while the regulatory mechanism of tuberization time(TT)is still unclear.In this study,two tetraploid cultivars,Zhongshu 3(Z3)and Zhongshu 18(Z18),with short and long TT respectively,were examined to reveal regulatory genes related to TT using RNA sequencing of tissue samples taken during stolon occurrence,stolon swelling and tuber formation.Cluster analysis showed that the gene expression patterns at the stolon swelling and tuber formation stages were significantly different from those at stolon occurrence in both Z3 and Z18.Therefore,we screened the differentially expressed genes(DEGs)at stolon swelling and tuber formation and compared them to those at stolon occurrence.A total of 3085 DEGs were specifically identified and analyzed according to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment,and DEGs involved in starch and sucrose metabolism,plant hormone signal transduction and plant circadian clock were significantly enriched.The circadian clock genes were significantly differentially expressed between Z3 and Z18,revealing an important role for the plant circadian pathway in regulating TT.Furthermore,three candidate genes,StGI,StPRR and StEFM involved in circadian regulation and significantly differentially expressed between Z3 and Z18,were discovered and confirmed by qRT-PCR.The results provide valuable information for understanding the regulatory mechanisms of potato TT and represent a step toward breeding early-maturing potato cultivars.展开更多
Eye depth is an important agronomic trait affecting tubers'appearance,quality,and processing suitability.Hence,cultivating varieties with uniform shapes and shallow eye depth are important goals for potato breedin...Eye depth is an important agronomic trait affecting tubers'appearance,quality,and processing suitability.Hence,cultivating varieties with uniform shapes and shallow eye depth are important goals for potato breeding.In this study,based on the primary mapping of the tuber eyedepth locus using a small primary-segregating population,a large secondary-segregating population with 2100 individuals was used to map the eye-depth locus further.A major quantitative trait locus for eye-depth on chromosome 10 was identified(designated qEyd10.1)using BSAseq and traditional QTL mapping methods.The qEyd10.1 could explain 55.0%of the eye depth phenotypic variation and was further narrowed to a 309.10 kb interval using recombinant analysis.To predict candidate genes,tissue sectioning and RNA-seq of the specific tuber tissues were performed.Genes encoding members of the peroxidase superfamily with likely roles in indole acetic acid regulation were considered the most promising candidates.These results will facilitate marker-assisted selection for the shallow-eye trait in potato breeding and provide a solid basis for eye-depth gene cloning and the analysis of tuber eye-depth regulatory mechanisms.展开更多
[Objective] This study aimed to investigate the mutagenic effect of cobalt- 60 irradiation on potato. [Method] Potato tubers of Favorita and Zhongshu No.3 were irradiated with 5, 10, 20, 30, 50 and 70 Gy of cobalt-60 ...[Objective] This study aimed to investigate the mutagenic effect of cobalt- 60 irradiation on potato. [Method] Potato tubers of Favorita and Zhongshu No.3 were irradiated with 5, 10, 20, 30, 50 and 70 Gy of cobalt-60 γ-ray respectively, to explore the mutagenic effect of different doses of γ-ray heavy ion irradiation on potato. [Result] The results showed that the emergence rate, seedling rate, plant growth, yield and commodity of potato varied after irradiated with different doses of cobalt-60 γ-ray; 10Gy of cobalt-60 irradiation played a positive effect on the growth and development of potato, while high doses played a negative effect on the growth and development of potato. After cobalt-60 irradiation, the botanical traits of M1 gen- eration varied greatly, resulting in a number of beneficial mutation traits; some traits of M2 and M3 generations became stably inherited. [Conclusion] Cobalt-60 irradiation breeding is conducive to the variety improvement and germplasm innovation as an effective means of genetic improvement for potato.展开更多
Phytohormones, auxins in particular, play an important role in plant development and productivity. Earlier data showed positive impact of exogenous auxin on potato (Solanum tuberosum L.) tuberization. The aim of this ...Phytohormones, auxins in particular, play an important role in plant development and productivity. Earlier data showed positive impact of exogenous auxin on potato (Solanum tuberosum L.) tuberization. The aim of this study was to generate potato plants with increased auxin level predominantly in tubers. To this end, a pBinB33-tms1 vector was constructed harboring the Agrobacterium auxin biosynthesis gene tms1 fused to tuber-specific promoter of the class I patatin gene (B33-promoter) of potato. Among numerous independently generated B33:tms1 lines, those without visible differences from control were selected for detailed studies. In the majority of transgenic lines, tms1 gene transcription was detected, mostly in tubers rather than in shoots. Indoleacetic acid (IAA) content in tubers and the auxin tuber-to-shoot ratio were increased in tms1-expressing transformants. The organ-specific increase in auxin synthesis in B33:tms1-transformants accelerated and intensified the process of tuber formation, reduced the dose of carbohydrate supply required for in vitro tuberization, and decreased the photoperiodic dependence of tuber initiation. Overall, a positive correlation was observed between tms1 expression, IAA content in tubers, and stimulation of tuber formation. The revealed properties of B33:tms1 transformants imply an important role for auxin in potato tuberization and offer prospects to magnify potato productivity by a moderate organ-specific enhancement of auxin content.展开更多
[Objective] This study aimed to investigate the appropriate dose of 60^Co-γ irradiation for tubers of purple sweet potato.[Methods] The tubers of two purple sweet potato varieties Xuzi L-7 and Yuenanzi were used as e...[Objective] This study aimed to investigate the appropriate dose of 60^Co-γ irradiation for tubers of purple sweet potato.[Methods] The tubers of two purple sweet potato varieties Xuzi L-7 and Yuenanzi were used as experimental materials,and treated with 60^Co-γ irradiation at different doses(0,25,50,75,100,125 and 150 Gy) to determine the emergence rate,number of emerged seedlings per tuber and fresh weight per seedling.[Results] After the 60^Co-γ irradiation at different doses,the emergence period of tubers was postponed while the emergence rate,number of emerged seedlings per tuber and fresh weight per plant were decreased,and the differences between different varieties and different irradiation doses reached significance level.Compared with the control,the emergence period of tubers at irradiation doses above 25 Gy were postponed by 2,3,5,6 and 12 d,respectively.[Conclusion] The half lethal dose(LD50) of Xuzi L-7 was 66.73 Gy,and that of Yuenanzi was 74.96 Gy.展开更多
Starch degradation in cells is closely associated with cereal seed germination, photosynthesis in leaves, carbohydrate storage in tuber and tuberous roots, and fleshy fruit development. Based on previously reported ...Starch degradation in cells is closely associated with cereal seed germination, photosynthesis in leaves, carbohydrate storage in tuber and tuberous roots, and fleshy fruit development. Based on previously reported in vitro assays, β amylase is considered as one of the key enzymes catalyzing starch breakdown, but up to date its role in starch breakdown in living cells remains unclear because the enzyme was shown often extrachloroplastic in living cells. Recently we have shown for the first time that β_amylase is predominantly immuno_localized to plastids in living cells of developing apple fruit. But it remains to know whether this model of β_amylase compartmentation is more widespread in plant living cells. The present experiment, conducted in tuberous root of sweet potato ( Ipomea batatas Lam. cv. Xushu 18) and via immunogold electron_microscopy technique, showed that β amylase visualized by gold particles was predominantly localized in plastids especially at periphery of starch granules, but the gold particles were scarcely found in other subcellular compartments, indicating that the enzyme is subcellularly compartmented in the same zone as its starch substrates. The density of gold particles (β amylase) in plastids was increasing during growing season, but the predominantly plastid_distributed pattern of β amylase in cells was shown unchanged throughout the tuberous root development. These data prove that the enzyme is compartmented in its functional sites, and so provide evidence to support the possible widespread biological function of the enzyme in catalyzing starch breakdown in plant living cells or at least in living cells of plant storage organs.展开更多
The potato tuber moth(PTM),Phthorimaea operculella(Zeller),is one of the most economically significant insect pests for potato in both field and storage worldwide.To evaluate the infestation,reduction of potato yield ...The potato tuber moth(PTM),Phthorimaea operculella(Zeller),is one of the most economically significant insect pests for potato in both field and storage worldwide.To evaluate the infestation,reduction of potato yield and the control efficacy for PTM,field tests were conducted in two seasons by intercropping of potato as the host plant with maize as a non-host plant of PTM.Three intercropping patterns were tested,which were 2 rows of potatoes with either 2,3,or 4 rows of maize(abbreviated 2 P:2 M,2 P:3 M,and 2 P:4 M),and the monocropped potato as the control,2 rows of potatoes,without maize,(abbreviated 2 P:0 M).Results showed that the population and infestation of PTM in the 2 P:3 M intercropping pattern was significantly lower than those in 2 P:2 M,2 P:4 M and the monocropping pattern of 2 P:0 M,due to the enhancement of natural enemies.Cumulative mines and tunneling in potato leaves in 2 P:3 M intercropping were significantly lower than those in 2 P:2 M and 2 P:4 M patterns.The population of parasitoids and the parasitism rate of PTM in intercropping pattern of 2 P:3 M were significantly higher than that in intercropping pattern of 2 P:2 M,2 P:4 M and monocropping pattern of 2 P:0 M.We conclude that the potato intercropped with maize reduced the adult and larva populations,and reduced the damage from PTM by enhancing the number of parasitoids and the level of parasitism.The greatest population density of parasitoids and parasitism rate were in the intercropping pattern of 2 rows of potatoes with 3 rows of maize.These data indicate that the host/non-host intercropping patterns can be used as a biological control tactic against PTM by enhancing the density of natural enemies in the agro-ecosystems.展开更多
Knowledge about crop growth processes in relation to N limitation is necessary to optimize N management in farming system. Plant-based diagnostic method, for instance nitrogen nutrition index (NNI) were used to dete...Knowledge about crop growth processes in relation to N limitation is necessary to optimize N management in farming system. Plant-based diagnostic method, for instance nitrogen nutrition index (NNI) were used to determine the crop nitrogen status. This study determines the relationship of NNI with agronomic nitrogen use efficiency (AEN), tuber yield, radiation use efficiency (RUE) and leaf parameters including leaf area index (LAI), areal leaf N content (NJ and leaf N concentration (N0. Potatoes were grown in field at three N levels: no N (N 1), 150 kg N ha^-1 (N2), 300 kg N ha^-1 (N3). N deficiency was quantified by NNI and RUE was generally calculated by estimating of the light absorbance on leaf area. NNI was used to evaluate the N effect on tuber yield, RUE, LAI, NAL, and NL. The results showed that NNI was negatively correlated with AEN, N deficiencies (NNI〈 1) which occurred for N 1 and N2 significantly reduced LAI, NL and tuber yield; whereas the N deficiencies had a relative small effect on NAL and RUE. To remove any effect other than N on these parameters, the actual ratio to maximum values were calculated for each developmental linear relationships were obtained between NNI and tuber RUE to NNI. stage of potatoes. When the NNI ranged from 0.4 to 1, positive yield, LAI, NL, while a nonlinear regression fitted the response of展开更多
Potato grows in most part of China, it achieves higher yield and better quality in Gansu Province than in others. With global warming, its growth duration has been prolonged and sowing date become earlier than before....Potato grows in most part of China, it achieves higher yield and better quality in Gansu Province than in others. With global warming, its growth duration has been prolonged and sowing date become earlier than before. Therefore, to regulate its sowing date and growing period is of great significance for better harvest. In this study, experiments were conducted with six sowing-date treatments of potato in Dingxi, which is in the Loess Plateau of central Gansu Province in Northwest China in 2010. The growth period, morphological index and change in yield and their relationships with temperature, precipitation, and other climatic factors were investigated for each treatment. Results show that the crop with different sowing dates experienced different climate conditions, leading to distinct growth duration, plant height, and leaf area index. The growth duration was shortened due to a delay in sowing date. For each 15-day delay in sowing, the growth duration was reduced by 12 days on average. A significant linear relationship was found between numbers of days either from seeding to emergence or from flowering to harvest and mean temperature over the corresponding period. Dry matter accumulation, tuber fresh weight, and final yield were all decreased because of insufficient cumulative temperature over the shorter growing periods. Marked differences in tuber yield were discovered among the six treatments of sowing date, the potato planted on May 27 giving the highest yield. The potato planted either earlier or later would produce invariably lower yield than the treatment of May 27. Late May therefore can be taken as the optimum sowing time of potato in this region because the crop can fully utilize thermal resource. We conclude that to postpone sowing time is a good practice for potato production to adapt to climate warming in the Loess Plateau of central Gansu, China.展开更多
Tuber starch content and plant maturity are two important agronomic traits of potato. To investigate the complex genetic basis of these traits in the cultivated potato, as well as the relationship between them, we dev...Tuber starch content and plant maturity are two important agronomic traits of potato. To investigate the complex genetic basis of these traits in the cultivated potato, as well as the relationship between them, we developed a linkage map in a tetraploid population of 192 clones derived from the cross Longshu 8 × Zaodabai and mapped quantitative trait loci(QTL) for tuber starch content and plant maturity using data collected in three diverse environments over two years. We detected eleven QTL for tuber starch content distributed on seven chromosomes, of which four, on chromosomes I, II, and VIII, were expressed in at least three environments. For plant maturity, we identified six QTL on chromosomes II, IV,V, VII, and XI, one of which, on chromosome V, showed LOD peaks ranging from 45.2 to 62.5 cM and explained 21.6%–26.6% of phenotypic variation was expressed in five of the six environments. Because the reproducible QTL for plant maturity and tuber starch content mapped to different chromosomes and neither overlapping QTL, nor any genetic interaction between QTL were detected, we infer that tuber starch content and plant maturity are controlled by independent genetic loci. This inference supports the prospect of breeding potato for both early maturity and high starch content.展开更多
The MYB transcription factor is one of the largest gene families in plants,playing an important role in regulating plant growth,development,response to stress,senescence,and especially the anthocyanin biosynthesis.In ...The MYB transcription factor is one of the largest gene families in plants,playing an important role in regulating plant growth,development,response to stress,senescence,and especially the anthocyanin biosynthesis.In this study,A total of 217 MYB genes,including 901R-MYBs,124 R2R3-MYBs,and 3 R1R2R3-MYBs have been identified from the potato genome.The 1R-MYB and R2R3-MYB family members could be divided into 20 and 35 subgroups respectively.Analysis of gene structure and protein motifs revealed that members within the same subgroup presented similar exon/intron and motif organization,further supporting the results of phylogenetic analysis.Potato is an ideal plant to reveal the tissue-specific anthocyanins biosynthesis regulated by MYB,as the anthocyanins could be accumulated in different tissues,showing colorful phenotypes.Five pairs of colored and colorless tissues,stigma,petal,stem,leaf,and tuber flesh,were applied to the transcriptomic analysis.A total of 70 MYB genes were found to be differentially expressed between colored and colorless tissues,and these differentially expressed genes were suspected to regulate the biosynthesis of anthocyanin of different tissues.Co-expression analysis identified numerous potential interactive regulators of anthocyanins biosynthesis,involving 39 MYBs,24 bHLHs,2 WD-repeats,and 29 biosynthesis genes.Genome-wide association study(GWAS)of tuber flesh color revealed amajor signal at the end of Chromosome 10,which was co-localized with reported I gene(StMYB88),controlling tuber peel color.Analyses of DEGs(Differentially Expression Genes)revealed that both StMYB88 and StMYB89 were closely related to regulating anthocyanin biosynthesis of tuber flesh.This work offers a comprehensive overview of the MYB family in potato and will lay a foundation for the functional validation of these genes in the tissue-specific regulation of anthocyanin biosynthesis.展开更多
The effects of soil aeration on physiological characters and root tuber yield of Ipomoea batatas (L.) Lam. CV Lushu7 and Xushu18 were studied. The results showed that soil aeration improvement could increase ATP conte...The effects of soil aeration on physiological characters and root tuber yield of Ipomoea batatas (L.) Lam. CV Lushu7 and Xushu18 were studied. The results showed that soil aeration improvement could increase ATP content and ATPase activity in functional leaves and root tubers and ABA content in root tubers. It also accelerated the transportation of 14C-photosynthate from leaves to root tubers and enhanced dry matter distribution in root tubers and thus root tuber yield was significantly raised. The role of ATP, ATPase and ABA in accelerating the transportation of 14C-photosynthate was discussed based on the changes of soluble carbonhydrate content in sweet potato plant.展开更多
According to previous analysis, some properties bounding up with tuber yield were investigated. The results showed that tuber average weight, plastid Mg2 + -ATPase activity, plastid Ca2 + -ATPase activity, mitochondri...According to previous analysis, some properties bounding up with tuber yield were investigated. The results showed that tuber average weight, plastid Mg2 + -ATPase activity, plastid Ca2 + -ATPase activity, mitochondria Mg2 + -ATPase activity, total soluble protein content, tuber average diameter, and Q-enzyme activity were important factors determining the tuber yield. The linear regression equation was:Y = 0.5211 + 0.0595X(1)+0.8389X(2) +0.0882X(3) -0.0073X(4) +0.1449X(5) +0.3510X(6) +0.0031X(7) -0.00003X(8) + 0.3412X(9) + 0.0127X(10) + 0.2904X(ll) + 0.0570X(12) + 0.0159X(13) + 0.3585X(14) + 0.0134X(15) - 0.1012X(16). At the same time, the relation between several important properties and soluble protein fractions were analyzed.展开更多
Potato is one of the priority vegetable crops in the highlands of Eritrea growing as a key component in the livelihood systems of farmers. Potato requires a variety of balanced plant mineral nutrients for growth and d...Potato is one of the priority vegetable crops in the highlands of Eritrea growing as a key component in the livelihood systems of farmers. Potato requires a variety of balanced plant mineral nutrients for growth and development without which yield and qualities of tubers are reduced. Potato growers in Eritrea commonly use Di-ammonium Phosphate, Urea and Farmyard manure while potassium fertilizers are overlooked assuming that the soil is developed from K rich parent material and contains sufficient amount of K to support crop growth. However this assumption is based on the result obtained forty-seven years ago. As a result the yield and quality of potato produced is very low as compared with international standards. Therefore the present experiment was conducted to assess the effect of potassium levels on growth and productivity of potato varieties at Hamelmalo Agricultural College, Eritrea. The experiment was conducted in factorial Randomized Complete Block Design with fifteen treatment combinations of three varieties (Ajiba, Zafira and Picasso) and five potassium levels (0, 75, 150, 225 and 300 kg K<sub>2</sub>O/ha) replicated thrice. The results of the study showed that both variety and potassium had significant effect on growth and yield parameters. Aerial stem number, leaf number per plant and plant height were increased with increasing K levels from 0 to 150 kg while number of days to maturity was increased in the range of 0 - 300 kg K<sub>2</sub>O/ha. The result also indicated that variety Ajiba treated with 300 kg K<sub>2</sub>O/ha produced significantly highest tuber weight (1.14 kg) per plant and tuber yield of 49.38 t/ha. The economic analysis result revealed that maximum gross margin 13,665.816 USD/ha was obtained from the application of 300 kg K<sub>2</sub>O/ha. On the whole, it gives an impression that using potassium fertilizer according to soil requirements will have good influence on growth and tuber yield.展开更多
Potato crop is the fourth main food crops in the world after maize, rice and wheat. It is characterized by specific temperature requirements and develops best at about 20°C. Forecasts of global warming prompt us ...Potato crop is the fourth main food crops in the world after maize, rice and wheat. It is characterized by specific temperature requirements and develops best at about 20°C. Forecasts of global warming prompt us to study the tolerance of potato genotypes to heat during the growing season. The aim of this work was to assess the response of chosen potato cultivars to high temperature during the different stages of plant growth under conditions of good soil moisture and drought. The impact of high temperature 32°C/25°C on potato plants was determined in pot experiment in three growth stages. A main measure of tolerance of the potato cultivars to high temperature during the growing season was an evaluation of the yield in relation to the Control combination. Here we demonstrated that tested potato cultivar’s response to high temperature during the growing season is dependent on the growth stage. The earlier it occurs, the more negative its impact on the growth and yield of potatoes is.展开更多
[Objective] The aim was to study the characteristics of accumulative potato biomass in different sowing dates and their relationships with the climate factors in Tianshui City.[Method] Based on the potato sowing exper...[Objective] The aim was to study the characteristics of accumulative potato biomass in different sowing dates and their relationships with the climate factors in Tianshui City.[Method] Based on the potato sowing experiment by installments in Tianshui agrometeorological experiment station in 2009,the potato's growth periods in every sowing date were contrasted with the average sowing period.Moreover,the climate resources' occupied amounts,the accumulative progresses of tuber's fresh biomass in every growth period were contrasted with the average sowing period.[Result] The results showed that the days of whole growth period in every sowing date tended to be same with the average period.The accumulative temperature's occupied amounts of every critical temperature had little difference,but the solar radiation and precipitation had great difference.The nonlinearity correlation between tuber's fresh biomass accumulation and the accumulative temperature (≥10℃) was obvious.When the accumulative temperature(≥10℃) was about 1 100℃,it was the turning point which the accumulative velocity of tuber's fresh biomass changed.The accumulation of tuber's fresh biomass in every sowing date had little difference before the inflorescence formation period.After the inflorescence formation period,the accumulative velocity of potato tuber's fresh biomass in the sowing date which was 7 days later than the average sowing period was greater than other sowing dates.[Conclusion] The optimum sowing date of potato should be in the end of early April.It had the negative effects to promote potato's yield by sowing early and too late.展开更多
Potato(Solanum tuberosum L.)is an important crop throughout the world.An uncharacterized disease has been observed on potato plants during the growing season and tubers during the storage period from Nileke County,Qit...Potato(Solanum tuberosum L.)is an important crop throughout the world.An uncharacterized disease has been observed on potato plants during the growing season and tubers during the storage period from Nileke County,Qitai County and other locations in Xinjiang,China.A particular fungus was consistently isolated from the infected potato plants and tubers.Based on its morphology,molecular characteristics,pathogenicity test and internal transcribed spacer(ITS)sequence,the pathogens was identified as Galactomyces candidum F12.Further study also showed that the hyphae and conidia of the pathogenic fungus grew faster as the temperature was 30℃,pH was 7,soluble starch was used as optimal carbon source and yeast powder as optimal nitrogen source.In addition,12-h continuous ilumination light was beneficial to the hyphal growth,while 24-h continuous ilumination was beneficial to the sporulation of the strain at 30℃.To our knowledge,this is the first report of Galactomyces candidum causing leaf wilt and postharvest tuber rot on potato in China.展开更多
文摘A field trial was conducted to investigate the changes of endogenous hormone concentration (EHC) during formation and thickening of tuberous roots in sweet potato (Ipomoea batatas L.) of different genotypes: Xushu 18, Minamiyutaka, and L trifida-K123. The results of this study suggested that the concentrations of zeatin riboside (ZR), dihydro-zeatin riboside (DHZR), abscisic acid (ABA), indole-3-acetic acid (IAA), and isopentenyl-adenine (IPA) of Xushu 18 and Minamiyutaka were significantly higher than those of I. trifida-K123. Dry tuberous root yields were positively correlated with the concentration of ABA, ZR, and DHZR at 1 or 5% significant level, but were not obviously correlated with the concentrations of IAA, IPA, and GA4. The concentrations of ABA, ZR and DHZR played very important roles in the tuberous root formation and thickening in sweet potato. The concentrations of ZR, DHZR, ABA, and IAA in the upper or inner portion of tuberous roots were significantly higher than those toward the end of the root or its outer portion. Meanwhile, EHC of large-sized tuberous roots were significantly higher than those of medium- or small-sized tubers during the early thickening period. In the rapid thickening period of tuberous roots, EHC of medium-sized tubers were the highest, However, at the late-thickening period, EHC of small-sized tubers ranked the highest.
文摘The IAA, GA3, iPA, ZR and ABA contents in sweet potato leaves under drought conditions were determined by the method of ELISA, and the relationship between these endogenous hormones and drought resistance of different sweet potato varieties were studied. The results showed the IAA, GA3, iPA and ZR contents in sweet potato leaves decreased, but ABA contents increased obviously. The stronger the drought resistance of the variety was, the more IAA, GA3, iPA and ZR contents decreased and the less ABA contents increased. Their relative contents correlated significantly negatively(r were -0.9070, -0.9493, -0.9509, -0.8674 and -0.9117 respectively)to drought-resistability.
基金funded by the Scientific Research Fund of College of Science&Technology,Ningbo University for the Introduction of High-level Talents,China(RC190006)。
文摘Red and blue light illumination has been reported to significantly affect plantlet growth.Potato is an important food and feed crop in the world and potato plantlet cultured in vitro plays an important role in potato production.However,few studies have documented the effects of red and blue light on the growth of potato plantlets revealed at the transcriptome level.The objective of this study was to determine the growth and physiological responses of potato plantlets cultured in vitro under monochromatic red(RR),monochromatic blue(BB)as well as combined red and blue(RB)LEDs using the RNA-Seq technique.In total,3150 and 814 differentially expressed genes(DEGs)were detected in potato plantlets under RR and BB,respectively,compared to RB(used as control).Compared to the control,the DEGs enriched in"photosynthesis"and"photosynthesis-antenna proteins"metabolic pathways were up-regulated and down-regulated by BB and RR,respectively,which might be responsible for the increases and decreases of maximum quantum yield(F_(v)/F_(m)),photochemical quantum yield(φ_(PSII)),photochemical quenching(q_(P))and electron transfer rate(ETR)in BB and RR,respectively.Potato plantlets exhibited dwarfed stems and extended leaves under BB,whereas elongated stems and small leaves were induced under RR.These dramatically altered plantlet phenotypes were associated with variable levels of endogenous plant hormones gibberellin(GAs),indoleacetic acid(IAA)and cytokinins(CKs),as assessed in stems and leaves of potato plantlets.In addition,monochromatic red and blue LEDs trigged the opposite expression profiles of DEGs identified in the"plant hormone signal transduction"metabolic pathway,which were closely related to the endogenous plant hormone levels in potato plantlets.Our results provide insights into the responses of potato plantlets cultured in vitro to red and blue LEDs at the transcriptomic level and may contribute to improvements in the micro-propagation of potato plantlets cultured in vitro from the light spectrum aspect.
基金This research was funded by the National Natural Science Foundation of China(Grant No.31771860)National Key R&D Program of China(Grant No.2017YFD0101905)China Agriculture Research System(CARS-09).
文摘Early tuberization,a short period from stolon occurrence to tuber formation,is one of the major characteristics of a good early-maturing potato cultivar,while the regulatory mechanism of tuberization time(TT)is still unclear.In this study,two tetraploid cultivars,Zhongshu 3(Z3)and Zhongshu 18(Z18),with short and long TT respectively,were examined to reveal regulatory genes related to TT using RNA sequencing of tissue samples taken during stolon occurrence,stolon swelling and tuber formation.Cluster analysis showed that the gene expression patterns at the stolon swelling and tuber formation stages were significantly different from those at stolon occurrence in both Z3 and Z18.Therefore,we screened the differentially expressed genes(DEGs)at stolon swelling and tuber formation and compared them to those at stolon occurrence.A total of 3085 DEGs were specifically identified and analyzed according to Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment,and DEGs involved in starch and sucrose metabolism,plant hormone signal transduction and plant circadian clock were significantly enriched.The circadian clock genes were significantly differentially expressed between Z3 and Z18,revealing an important role for the plant circadian pathway in regulating TT.Furthermore,three candidate genes,StGI,StPRR and StEFM involved in circadian regulation and significantly differentially expressed between Z3 and Z18,were discovered and confirmed by qRT-PCR.The results provide valuable information for understanding the regulatory mechanisms of potato TT and represent a step toward breeding early-maturing potato cultivars.
基金funded by the National Natural Science Foundation of China(Grant No.31801421)the Chinese Academy of Agricultural Sciences Innovation Project(Grant No.CAAS-ASTIPIVFCAAS).
文摘Eye depth is an important agronomic trait affecting tubers'appearance,quality,and processing suitability.Hence,cultivating varieties with uniform shapes and shallow eye depth are important goals for potato breeding.In this study,based on the primary mapping of the tuber eyedepth locus using a small primary-segregating population,a large secondary-segregating population with 2100 individuals was used to map the eye-depth locus further.A major quantitative trait locus for eye-depth on chromosome 10 was identified(designated qEyd10.1)using BSAseq and traditional QTL mapping methods.The qEyd10.1 could explain 55.0%of the eye depth phenotypic variation and was further narrowed to a 309.10 kb interval using recombinant analysis.To predict candidate genes,tissue sectioning and RNA-seq of the specific tuber tissues were performed.Genes encoding members of the peroxidase superfamily with likely roles in indole acetic acid regulation were considered the most promising candidates.These results will facilitate marker-assisted selection for the shallow-eye trait in potato breeding and provide a solid basis for eye-depth gene cloning and the analysis of tuber eye-depth regulatory mechanisms.
基金Supported by Youth Fund of President of Anhui Academy of Agricultural Sciences (11B0324)~~
文摘[Objective] This study aimed to investigate the mutagenic effect of cobalt- 60 irradiation on potato. [Method] Potato tubers of Favorita and Zhongshu No.3 were irradiated with 5, 10, 20, 30, 50 and 70 Gy of cobalt-60 γ-ray respectively, to explore the mutagenic effect of different doses of γ-ray heavy ion irradiation on potato. [Result] The results showed that the emergence rate, seedling rate, plant growth, yield and commodity of potato varied after irradiated with different doses of cobalt-60 γ-ray; 10Gy of cobalt-60 irradiation played a positive effect on the growth and development of potato, while high doses played a negative effect on the growth and development of potato. After cobalt-60 irradiation, the botanical traits of M1 gen- eration varied greatly, resulting in a number of beneficial mutation traits; some traits of M2 and M3 generations became stably inherited. [Conclusion] Cobalt-60 irradiation breeding is conducive to the variety improvement and germplasm innovation as an effective means of genetic improvement for potato.
基金supported by the Russian Science Foundation (grant no. 14-14-01095)partly (until July, 2014) by the Program of the Presidium of the Russian Academy of Sciences " Molecular and Cell Biology "
文摘Phytohormones, auxins in particular, play an important role in plant development and productivity. Earlier data showed positive impact of exogenous auxin on potato (Solanum tuberosum L.) tuberization. The aim of this study was to generate potato plants with increased auxin level predominantly in tubers. To this end, a pBinB33-tms1 vector was constructed harboring the Agrobacterium auxin biosynthesis gene tms1 fused to tuber-specific promoter of the class I patatin gene (B33-promoter) of potato. Among numerous independently generated B33:tms1 lines, those without visible differences from control were selected for detailed studies. In the majority of transgenic lines, tms1 gene transcription was detected, mostly in tubers rather than in shoots. Indoleacetic acid (IAA) content in tubers and the auxin tuber-to-shoot ratio were increased in tms1-expressing transformants. The organ-specific increase in auxin synthesis in B33:tms1-transformants accelerated and intensified the process of tuber formation, reduced the dose of carbohydrate supply required for in vitro tuberization, and decreased the photoperiodic dependence of tuber initiation. Overall, a positive correlation was observed between tms1 expression, IAA content in tubers, and stimulation of tuber formation. The revealed properties of B33:tms1 transformants imply an important role for auxin in potato tuberization and offer prospects to magnify potato productivity by a moderate organ-specific enhancement of auxin content.
基金Supported by "12th Five-Year Plan" Breeding Project of Crops and Live stock of Sichuan Province~~
文摘[Objective] This study aimed to investigate the appropriate dose of 60^Co-γ irradiation for tubers of purple sweet potato.[Methods] The tubers of two purple sweet potato varieties Xuzi L-7 and Yuenanzi were used as experimental materials,and treated with 60^Co-γ irradiation at different doses(0,25,50,75,100,125 and 150 Gy) to determine the emergence rate,number of emerged seedlings per tuber and fresh weight per seedling.[Results] After the 60^Co-γ irradiation at different doses,the emergence period of tubers was postponed while the emergence rate,number of emerged seedlings per tuber and fresh weight per plant were decreased,and the differences between different varieties and different irradiation doses reached significance level.Compared with the control,the emergence period of tubers at irradiation doses above 25 Gy were postponed by 2,3,5,6 and 12 d,respectively.[Conclusion] The half lethal dose(LD50) of Xuzi L-7 was 66.73 Gy,and that of Yuenanzi was 74.96 Gy.
文摘Starch degradation in cells is closely associated with cereal seed germination, photosynthesis in leaves, carbohydrate storage in tuber and tuberous roots, and fleshy fruit development. Based on previously reported in vitro assays, β amylase is considered as one of the key enzymes catalyzing starch breakdown, but up to date its role in starch breakdown in living cells remains unclear because the enzyme was shown often extrachloroplastic in living cells. Recently we have shown for the first time that β_amylase is predominantly immuno_localized to plastids in living cells of developing apple fruit. But it remains to know whether this model of β_amylase compartmentation is more widespread in plant living cells. The present experiment, conducted in tuberous root of sweet potato ( Ipomea batatas Lam. cv. Xushu 18) and via immunogold electron_microscopy technique, showed that β amylase visualized by gold particles was predominantly localized in plastids especially at periphery of starch granules, but the gold particles were scarcely found in other subcellular compartments, indicating that the enzyme is subcellularly compartmented in the same zone as its starch substrates. The density of gold particles (β amylase) in plastids was increasing during growing season, but the predominantly plastid_distributed pattern of β amylase in cells was shown unchanged throughout the tuberous root development. These data prove that the enzyme is compartmented in its functional sites, and so provide evidence to support the possible widespread biological function of the enzyme in catalyzing starch breakdown in plant living cells or at least in living cells of plant storage organs.
基金supported by the National Key Research and Development Program of China (2018YFD0200703 and 2018YFD0200802)the National Natural Science Foundation of China (3176059 and 31660537)
文摘The potato tuber moth(PTM),Phthorimaea operculella(Zeller),is one of the most economically significant insect pests for potato in both field and storage worldwide.To evaluate the infestation,reduction of potato yield and the control efficacy for PTM,field tests were conducted in two seasons by intercropping of potato as the host plant with maize as a non-host plant of PTM.Three intercropping patterns were tested,which were 2 rows of potatoes with either 2,3,or 4 rows of maize(abbreviated 2 P:2 M,2 P:3 M,and 2 P:4 M),and the monocropped potato as the control,2 rows of potatoes,without maize,(abbreviated 2 P:0 M).Results showed that the population and infestation of PTM in the 2 P:3 M intercropping pattern was significantly lower than those in 2 P:2 M,2 P:4 M and the monocropping pattern of 2 P:0 M,due to the enhancement of natural enemies.Cumulative mines and tunneling in potato leaves in 2 P:3 M intercropping were significantly lower than those in 2 P:2 M and 2 P:4 M patterns.The population of parasitoids and the parasitism rate of PTM in intercropping pattern of 2 P:3 M were significantly higher than that in intercropping pattern of 2 P:2 M,2 P:4 M and monocropping pattern of 2 P:0 M.We conclude that the potato intercropped with maize reduced the adult and larva populations,and reduced the damage from PTM by enhancing the number of parasitoids and the level of parasitism.The greatest population density of parasitoids and parasitism rate were in the intercropping pattern of 2 rows of potatoes with 3 rows of maize.These data indicate that the host/non-host intercropping patterns can be used as a biological control tactic against PTM by enhancing the density of natural enemies in the agro-ecosystems.
基金supported by the National Key Technology R&D Program (2011BAD12B03)
文摘Knowledge about crop growth processes in relation to N limitation is necessary to optimize N management in farming system. Plant-based diagnostic method, for instance nitrogen nutrition index (NNI) were used to determine the crop nitrogen status. This study determines the relationship of NNI with agronomic nitrogen use efficiency (AEN), tuber yield, radiation use efficiency (RUE) and leaf parameters including leaf area index (LAI), areal leaf N content (NJ and leaf N concentration (N0. Potatoes were grown in field at three N levels: no N (N 1), 150 kg N ha^-1 (N2), 300 kg N ha^-1 (N3). N deficiency was quantified by NNI and RUE was generally calculated by estimating of the light absorbance on leaf area. NNI was used to evaluate the N effect on tuber yield, RUE, LAI, NAL, and NL. The results showed that NNI was negatively correlated with AEN, N deficiencies (NNI〈 1) which occurred for N 1 and N2 significantly reduced LAI, NL and tuber yield; whereas the N deficiencies had a relative small effect on NAL and RUE. To remove any effect other than N on these parameters, the actual ratio to maximum values were calculated for each developmental linear relationships were obtained between NNI and tuber RUE to NNI. stage of potatoes. When the NNI ranged from 0.4 to 1, positive yield, LAI, NL, while a nonlinear regression fitted the response of
基金supported by the Scientific Research and Innovation Plan for College Graduates of Jiangsu Province, China(CXZZ13_0521)
文摘Potato grows in most part of China, it achieves higher yield and better quality in Gansu Province than in others. With global warming, its growth duration has been prolonged and sowing date become earlier than before. Therefore, to regulate its sowing date and growing period is of great significance for better harvest. In this study, experiments were conducted with six sowing-date treatments of potato in Dingxi, which is in the Loess Plateau of central Gansu Province in Northwest China in 2010. The growth period, morphological index and change in yield and their relationships with temperature, precipitation, and other climatic factors were investigated for each treatment. Results show that the crop with different sowing dates experienced different climate conditions, leading to distinct growth duration, plant height, and leaf area index. The growth duration was shortened due to a delay in sowing date. For each 15-day delay in sowing, the growth duration was reduced by 12 days on average. A significant linear relationship was found between numbers of days either from seeding to emergence or from flowering to harvest and mean temperature over the corresponding period. Dry matter accumulation, tuber fresh weight, and final yield were all decreased because of insufficient cumulative temperature over the shorter growing periods. Marked differences in tuber yield were discovered among the six treatments of sowing date, the potato planted on May 27 giving the highest yield. The potato planted either earlier or later would produce invariably lower yield than the treatment of May 27. Late May therefore can be taken as the optimum sowing time of potato in this region because the crop can fully utilize thermal resource. We conclude that to postpone sowing time is a good practice for potato production to adapt to climate warming in the Loess Plateau of central Gansu, China.
基金supported by Earmarked Fund for China Agriculture Research System(CARS-09-P07)the National Natural Science Foundation of China(31160299,31760410)
文摘Tuber starch content and plant maturity are two important agronomic traits of potato. To investigate the complex genetic basis of these traits in the cultivated potato, as well as the relationship between them, we developed a linkage map in a tetraploid population of 192 clones derived from the cross Longshu 8 × Zaodabai and mapped quantitative trait loci(QTL) for tuber starch content and plant maturity using data collected in three diverse environments over two years. We detected eleven QTL for tuber starch content distributed on seven chromosomes, of which four, on chromosomes I, II, and VIII, were expressed in at least three environments. For plant maturity, we identified six QTL on chromosomes II, IV,V, VII, and XI, one of which, on chromosome V, showed LOD peaks ranging from 45.2 to 62.5 cM and explained 21.6%–26.6% of phenotypic variation was expressed in five of the six environments. Because the reproducible QTL for plant maturity and tuber starch content mapped to different chromosomes and neither overlapping QTL, nor any genetic interaction between QTL were detected, we infer that tuber starch content and plant maturity are controlled by independent genetic loci. This inference supports the prospect of breeding potato for both early maturity and high starch content.
基金the National Natural Science Foundation of China(Grant No.31601756)the National Science Fund of Yunnan for Distinguished Young Scholars(Grant No.202001AV070003)。
文摘The MYB transcription factor is one of the largest gene families in plants,playing an important role in regulating plant growth,development,response to stress,senescence,and especially the anthocyanin biosynthesis.In this study,A total of 217 MYB genes,including 901R-MYBs,124 R2R3-MYBs,and 3 R1R2R3-MYBs have been identified from the potato genome.The 1R-MYB and R2R3-MYB family members could be divided into 20 and 35 subgroups respectively.Analysis of gene structure and protein motifs revealed that members within the same subgroup presented similar exon/intron and motif organization,further supporting the results of phylogenetic analysis.Potato is an ideal plant to reveal the tissue-specific anthocyanins biosynthesis regulated by MYB,as the anthocyanins could be accumulated in different tissues,showing colorful phenotypes.Five pairs of colored and colorless tissues,stigma,petal,stem,leaf,and tuber flesh,were applied to the transcriptomic analysis.A total of 70 MYB genes were found to be differentially expressed between colored and colorless tissues,and these differentially expressed genes were suspected to regulate the biosynthesis of anthocyanin of different tissues.Co-expression analysis identified numerous potential interactive regulators of anthocyanins biosynthesis,involving 39 MYBs,24 bHLHs,2 WD-repeats,and 29 biosynthesis genes.Genome-wide association study(GWAS)of tuber flesh color revealed amajor signal at the end of Chromosome 10,which was co-localized with reported I gene(StMYB88),controlling tuber peel color.Analyses of DEGs(Differentially Expression Genes)revealed that both StMYB88 and StMYB89 were closely related to regulating anthocyanin biosynthesis of tuber flesh.This work offers a comprehensive overview of the MYB family in potato and will lay a foundation for the functional validation of these genes in the tissue-specific regulation of anthocyanin biosynthesis.
文摘The effects of soil aeration on physiological characters and root tuber yield of Ipomoea batatas (L.) Lam. CV Lushu7 and Xushu18 were studied. The results showed that soil aeration improvement could increase ATP content and ATPase activity in functional leaves and root tubers and ABA content in root tubers. It also accelerated the transportation of 14C-photosynthate from leaves to root tubers and enhanced dry matter distribution in root tubers and thus root tuber yield was significantly raised. The role of ATP, ATPase and ABA in accelerating the transportation of 14C-photosynthate was discussed based on the changes of soluble carbonhydrate content in sweet potato plant.
基金the National Natural Science Foundation(39370486) the Laboratory of Vegetative Genetics and Physiology inthe Agricultural Ministry of P.R.China.
文摘According to previous analysis, some properties bounding up with tuber yield were investigated. The results showed that tuber average weight, plastid Mg2 + -ATPase activity, plastid Ca2 + -ATPase activity, mitochondria Mg2 + -ATPase activity, total soluble protein content, tuber average diameter, and Q-enzyme activity were important factors determining the tuber yield. The linear regression equation was:Y = 0.5211 + 0.0595X(1)+0.8389X(2) +0.0882X(3) -0.0073X(4) +0.1449X(5) +0.3510X(6) +0.0031X(7) -0.00003X(8) + 0.3412X(9) + 0.0127X(10) + 0.2904X(ll) + 0.0570X(12) + 0.0159X(13) + 0.3585X(14) + 0.0134X(15) - 0.1012X(16). At the same time, the relation between several important properties and soluble protein fractions were analyzed.
文摘Potato is one of the priority vegetable crops in the highlands of Eritrea growing as a key component in the livelihood systems of farmers. Potato requires a variety of balanced plant mineral nutrients for growth and development without which yield and qualities of tubers are reduced. Potato growers in Eritrea commonly use Di-ammonium Phosphate, Urea and Farmyard manure while potassium fertilizers are overlooked assuming that the soil is developed from K rich parent material and contains sufficient amount of K to support crop growth. However this assumption is based on the result obtained forty-seven years ago. As a result the yield and quality of potato produced is very low as compared with international standards. Therefore the present experiment was conducted to assess the effect of potassium levels on growth and productivity of potato varieties at Hamelmalo Agricultural College, Eritrea. The experiment was conducted in factorial Randomized Complete Block Design with fifteen treatment combinations of three varieties (Ajiba, Zafira and Picasso) and five potassium levels (0, 75, 150, 225 and 300 kg K<sub>2</sub>O/ha) replicated thrice. The results of the study showed that both variety and potassium had significant effect on growth and yield parameters. Aerial stem number, leaf number per plant and plant height were increased with increasing K levels from 0 to 150 kg while number of days to maturity was increased in the range of 0 - 300 kg K<sub>2</sub>O/ha. The result also indicated that variety Ajiba treated with 300 kg K<sub>2</sub>O/ha produced significantly highest tuber weight (1.14 kg) per plant and tuber yield of 49.38 t/ha. The economic analysis result revealed that maximum gross margin 13,665.816 USD/ha was obtained from the application of 300 kg K<sub>2</sub>O/ha. On the whole, it gives an impression that using potassium fertilizer according to soil requirements will have good influence on growth and tuber yield.
文摘Potato crop is the fourth main food crops in the world after maize, rice and wheat. It is characterized by specific temperature requirements and develops best at about 20°C. Forecasts of global warming prompt us to study the tolerance of potato genotypes to heat during the growing season. The aim of this work was to assess the response of chosen potato cultivars to high temperature during the different stages of plant growth under conditions of good soil moisture and drought. The impact of high temperature 32°C/25°C on potato plants was determined in pot experiment in three growth stages. A main measure of tolerance of the potato cultivars to high temperature during the growing season was an evaluation of the yield in relation to the Control combination. Here we demonstrated that tested potato cultivar’s response to high temperature during the growing season is dependent on the growth stage. The earlier it occurs, the more negative its impact on the growth and yield of potatoes is.
基金Supported by The Special Project of Service Industry in National Science & Technology Ministry (GYHY200806021)
文摘[Objective] The aim was to study the characteristics of accumulative potato biomass in different sowing dates and their relationships with the climate factors in Tianshui City.[Method] Based on the potato sowing experiment by installments in Tianshui agrometeorological experiment station in 2009,the potato's growth periods in every sowing date were contrasted with the average sowing period.Moreover,the climate resources' occupied amounts,the accumulative progresses of tuber's fresh biomass in every growth period were contrasted with the average sowing period.[Result] The results showed that the days of whole growth period in every sowing date tended to be same with the average period.The accumulative temperature's occupied amounts of every critical temperature had little difference,but the solar radiation and precipitation had great difference.The nonlinearity correlation between tuber's fresh biomass accumulation and the accumulative temperature (≥10℃) was obvious.When the accumulative temperature(≥10℃) was about 1 100℃,it was the turning point which the accumulative velocity of tuber's fresh biomass changed.The accumulation of tuber's fresh biomass in every sowing date had little difference before the inflorescence formation period.After the inflorescence formation period,the accumulative velocity of potato tuber's fresh biomass in the sowing date which was 7 days later than the average sowing period was greater than other sowing dates.[Conclusion] The optimum sowing date of potato should be in the end of early April.It had the negative effects to promote potato's yield by sowing early and too late.
基金Supported by the Basic Scientific Research Fund Project of the Public Welfare Scientific Research Institute of Xinjiang Autonomous Region,China(KY2018012,KY2019020)the Open Fund of Key Laboratory of Integrated Pest Management on Crop in Northwestern Oasis,Ministry of Agriculture and Rural Affairs,China(KFJJ202006).
文摘Potato(Solanum tuberosum L.)is an important crop throughout the world.An uncharacterized disease has been observed on potato plants during the growing season and tubers during the storage period from Nileke County,Qitai County and other locations in Xinjiang,China.A particular fungus was consistently isolated from the infected potato plants and tubers.Based on its morphology,molecular characteristics,pathogenicity test and internal transcribed spacer(ITS)sequence,the pathogens was identified as Galactomyces candidum F12.Further study also showed that the hyphae and conidia of the pathogenic fungus grew faster as the temperature was 30℃,pH was 7,soluble starch was used as optimal carbon source and yeast powder as optimal nitrogen source.In addition,12-h continuous ilumination light was beneficial to the hyphal growth,while 24-h continuous ilumination was beneficial to the sporulation of the strain at 30℃.To our knowledge,this is the first report of Galactomyces candidum causing leaf wilt and postharvest tuber rot on potato in China.