Plants show different growth responses to N sources supplied with either NH4^＋ or NO3^-. The uptake of different N sources also affects the rhizosphere pH and therefore the bioavallability of soil phosphorus, particu...Plants show different growth responses to N sources supplied with either NH4^＋ or NO3^-. The uptake of different N sources also affects the rhizosphere pH and therefore the bioavallability of soil phosphorus, particularly in alkaline soils. The plant growth, P uptake, and P availability in the rhizosphere of oat （Arena nuda L.） grown in hydroponics and in soil culture were investigated under supply with sole NH4^＋-N, sole NO3-N, or a combination. Sole NO^- -fed oat plants accumulated more biomass than sole NH4^＋ -fed ones. The highest biomass accumulation was observed when N was supplied with both NH^＋ -N and NO3^- -N. Growth of the plant root increased with the proportion of NO3^- in the cultural medium. Better root growth and higher root/shoot ratio were consistently observed in NO3^- fed plants. However, root vigor was the highest when N was supplied with NO3^- ＋NH4^＋. NH4^＋ supply reduced the rhizosphere pH but did not affect P uptake by plants grown in soils with CaHPO4 added as P source. No P deficiency was observed, and plant P concentrations were generally above 2 g kg^-1. P uptake was increased when N was supplied partly or solely as NO3^--N, similarly as biomass accumulation. The results suggested that oat was an NO3-preferring plant, and NO3^- -N was essential for plant growth and the maintenance of root absorption capacity. N supply with NH4^＋ -N did not improve P nutrition, which was most likely due to the absence of P deficiency.展开更多
Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activit...Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activities, nutritional con-tents, and flour pasting properties of OR kernels. Results showed that a peeling time of 20 s caused 16.13% β-glucan loss, while a peeling time 25 s caused 34.29% β-glucan loss in the kernels. OR kernels with a 20 s peeling treatment demonstrated significantly higher starch levels and kernel whiteness compared with normal oat kernels (P<0.01). It was also found that normal pressure steaming, autoclaved steaming and infrared roasting treatments could exterminate lipase activities in the OR kernels, and provide the OR kernels with significantly lower final viscosities and setback values than normal kernels (P<0.01).展开更多
Barley production has been constrained by various factors,of which loose smut(Ustilago nuda)is the main biotic factor.Molecular and agronomical screening analyses were evaluated to study the similarity levels and mark...Barley production has been constrained by various factors,of which loose smut(Ustilago nuda)is the main biotic factor.Molecular and agronomical screening analyses were evaluated to study the similarity levels and marker assisted selection associated with resistance to loose smut among eight barley genotypes using sequence-related amplified polymorphism(SRAP).Agronomical parameters during two consecutive 2021 and 2022 seasons were studied to identify their reaction to loose smut.The results exhibited significant differences among all studied genotypes for all studied characters,and the highest mean values for all studied traits were detected in Giza 136 and Giza 137.Six SRAP selected primer combinations were amplified and gave 56 total fragments,where primer combination me1+em3 gave the highest polymorphism(100%)and the highest polymorphic information content of PIC was 0.96.The dendrogram of SRAP markers had clustered all studied genotypes into two main clusters.Cluster I includes all the resistance genotypes Giza 136,Giza 137,Giza 123,Giza 132,Giza 138 and Line 2.However,cluster II includes only Line 1 and Line 3 as susceptible genotypes.Thus,SRAP marker could be efficiently used to assess genetic variation among barley genotypes and useful for barley germplasm management in terms of biodiversity protection and design of new crosses for loose smut breeding programs,and seed dressings are commonly used to prevent infected seed from developing smutted heads.Some effective seed dressings include Triticonazole,Black seed oil and gamma rays 150,200,250 Gy.The tested fungicide was highly effective in controlling the disease and gave more than 99%disease control with high grain yield while nature product as black seed oil and utilizing radiation gamma ray 250 GY was the most effective.Utilizing radiation and natural ingredients to manage loose barley smut is economical.展开更多
基金Project supported by the National Natural Science Foundation Council of China (No.30660086)the Natural Science Foundation of Inner Mongolia of China (No.200607010302)+2 种基金Hong Kong Research Grants Council (No.2465/05M)Hong Kong University Grants Committee (No.AOE/B-07/99)Hong Kong Baptist University Matching Research Fund.
文摘Plants show different growth responses to N sources supplied with either NH4^＋ or NO3^-. The uptake of different N sources also affects the rhizosphere pH and therefore the bioavallability of soil phosphorus, particularly in alkaline soils. The plant growth, P uptake, and P availability in the rhizosphere of oat （Arena nuda L.） grown in hydroponics and in soil culture were investigated under supply with sole NH4^＋-N, sole NO3-N, or a combination. Sole NO^- -fed oat plants accumulated more biomass than sole NH4^＋ -fed ones. The highest biomass accumulation was observed when N was supplied with both NH^＋ -N and NO3^- -N. Growth of the plant root increased with the proportion of NO3^- in the cultural medium. Better root growth and higher root/shoot ratio were consistently observed in NO3^- fed plants. However, root vigor was the highest when N was supplied with NO3^- ＋NH4^＋. NH4^＋ supply reduced the rhizosphere pH but did not affect P uptake by plants grown in soils with CaHPO4 added as P source. No P deficiency was observed, and plant P concentrations were generally above 2 g kg^-1. P uptake was increased when N was supplied partly or solely as NO3^--N, similarly as biomass accumulation. The results suggested that oat was an NO3-preferring plant, and NO3^- -N was essential for plant growth and the maintenance of root absorption capacity. N supply with NH4^＋ -N did not improve P nutrition, which was most likely due to the absence of P deficiency.
文摘Peeled naked oat kernels, named “oat rice” (OR) by Chinese food scientists and processors, are novel oat products in China. This study exam-ined the effects of steaming and roasting treat-ments on the enzyme activities, nutritional con-tents, and flour pasting properties of OR kernels. Results showed that a peeling time of 20 s caused 16.13% β-glucan loss, while a peeling time 25 s caused 34.29% β-glucan loss in the kernels. OR kernels with a 20 s peeling treatment demonstrated significantly higher starch levels and kernel whiteness compared with normal oat kernels (P<0.01). It was also found that normal pressure steaming, autoclaved steaming and infrared roasting treatments could exterminate lipase activities in the OR kernels, and provide the OR kernels with significantly lower final viscosities and setback values than normal kernels (P<0.01).
文摘Barley production has been constrained by various factors,of which loose smut(Ustilago nuda)is the main biotic factor.Molecular and agronomical screening analyses were evaluated to study the similarity levels and marker assisted selection associated with resistance to loose smut among eight barley genotypes using sequence-related amplified polymorphism(SRAP).Agronomical parameters during two consecutive 2021 and 2022 seasons were studied to identify their reaction to loose smut.The results exhibited significant differences among all studied genotypes for all studied characters,and the highest mean values for all studied traits were detected in Giza 136 and Giza 137.Six SRAP selected primer combinations were amplified and gave 56 total fragments,where primer combination me1+em3 gave the highest polymorphism(100%)and the highest polymorphic information content of PIC was 0.96.The dendrogram of SRAP markers had clustered all studied genotypes into two main clusters.Cluster I includes all the resistance genotypes Giza 136,Giza 137,Giza 123,Giza 132,Giza 138 and Line 2.However,cluster II includes only Line 1 and Line 3 as susceptible genotypes.Thus,SRAP marker could be efficiently used to assess genetic variation among barley genotypes and useful for barley germplasm management in terms of biodiversity protection and design of new crosses for loose smut breeding programs,and seed dressings are commonly used to prevent infected seed from developing smutted heads.Some effective seed dressings include Triticonazole,Black seed oil and gamma rays 150,200,250 Gy.The tested fungicide was highly effective in controlling the disease and gave more than 99%disease control with high grain yield while nature product as black seed oil and utilizing radiation gamma ray 250 GY was the most effective.Utilizing radiation and natural ingredients to manage loose barley smut is economical.
