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1.
Maria Antonia Machado Barbosa Kacilda Naomi Kuki Pedro Santos Peno Bengala Emilly dos Santos Pereira Angélica Fátima de Barros Sebastián Giraldo Montoya Leonardo Duarte Pimentel 《Journal of Agronomy and Crop Science》2020,206(2):263-276
Environmental conditions influence phenology and physiological processes of plants. It is common for maize and sorghum to be sown at two different periods: the first cropping (spring/summer) and the second cropping (autumn/winter). The phenological cycle of these crops varies greatly according to the planting season, and it is necessary to characterize the growth and development to facilitate the selection of the species best adapted to the environment. The aim of this study was to characterize phenological phases and physiological parameters in sorghum and maize plants as a function of environmental conditions from the first cropping and second cropping periods. Two parallel experiments were conducted with both crops. The phenological characterization was based on growth analyses (plant height, leaf area and photoassimilate partitioning) and gas exchange evaluations (net assimilation rate, stomatal conductance, transpiration and water-use efficiency). It was found that the vegetative stage (VS) for sorghum and maize plants was 7 and 21 days, respectively, longer when cultivated during the second cropping. In the first cropping, the plants were taller than in the second cropping, regardless of the crop. The stomatal conductance of sorghum plants fluctuated in the second cropping during the development period, while maize plants showed decreasing linear behaviour. Water-use efficiency in sorghum plants was higher during the second cropping compared with the first cropping. In maize plants, in the second cropping, the water-use efficiency showed a slight variation in relation to the first cropping. It was concluded that the environmental conditions as degree-days, temperature, photoperiod and pluvial precipitation influence the phenology and physiology of both crops during the first and the second cropping periods, specifically cycle duration, plant height, leaf area, net assimilation rate, stomatal conductance and water-use efficiency, indicating that both crops respond differentially to environmental changes during the growing season. 相似文献
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Classical “high-lysine” sorghum lines are characterized by smaller seeds than average, due to a decrease in prolamin synthesis and a subsequent decrease in yield. To exploit the natural variation in lysine content and to identify ecotypes with a seed lysine content higher than average, characterized by plump seeds, a method was developed based on root-growth inhibition of seeds growing on a medium containing aminoethylcysteine (AEC), a lysine analogue. By using a collection of sorghum mutants and ecotypes a correlation coefficient of 0.926 between root length and lysine content was established. This method, which uses the root length of plants growing on aec to indicate which lines have a potential elevated lysine content, can be applied for the screening of sorghum germplasm. Since this is a non-destructive method it can also be used at the individual seed level, for example for screening progenies of regenerated plants from in vitro culture to exploit the somaclonal variation. 相似文献
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向日葵[IIelianlhus anuus (L.)]是我国的重要经济作物。其花粉通常呈深浅程度不同的黄颜色。据我们掌握和查新资料,目前世界上尚未见有关白花粉方面的报道。1989年7月下旬至8月上旬,我们在吉林农业大学向日葵育种试验田的恢复系C8711群体中,先后发现4株白花粉突变体。暂分别定名为C8711—1、C8711—2、C8711—3和C8711—4。在进行人工套袋之前,此4株突变体已经在一定程度上发生了开放授粉,其中C8711—4开放授粉程度较轻。成熟时单独收获这4株突变体的种子,以进行有关遗传学研究,本文拟对白花粉突变的遗传学机理进行初步的探讨。 相似文献
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高梁不育系Tx3197A减数分裂中染色体行为 总被引:3,自引:0,他引:3
以Tx3197B和晋粱5号为对照,对Tx3197A进行了观察。结果发现,减数分裂前期Ⅰ和中期Ⅰ无明显异常。自后期Ⅰ开始,染色体行为出现了多类型的异常现象,导致减数分裂不能正常进行,无法形成花粉粒,从而产生雄性不育。 相似文献
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蜂花粉营养液的营养成分分析 总被引:4,自引:0,他引:4
蜂花粉营养液以油菜花粉和蜂蜜为原料,经过先进的生产工艺制备而成.本文主要对其营养成分进行了分析,该营养液的营养成分搭配合理,含有17种氨基酸,其中包括8种必需氨基酸,氨基酸总量为575.2 mg/100mL;钙31.90 mg/100mL、钾77.46 mg/100mL、钠6.16 mg/100mL、镁19.12 mg/100mL、锌0.14 mg/100mL、铁0.14 mg/100mL、锰0.13 mg/100mL、铜0.053 mg/100mL;尼克酸0.24 mg/100mL、维生素B2 0.01mg/100mL、维生素B6 0.74 mg/100mL、维生素C 0.75 mg/100mL. 相似文献
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试验将槐花蜂花粉进行振动磨超微粉碎破壁,分别按1 g/kg、5 g/kg、10 g/kg三个不同剂量混到蛋鸡饲料中,从7日龄开始饲喂至50日龄,每个剂量分两个试验,试验一用新城疫Ⅳ系疫苗免疫雏鸡,利用β-微量法监测血清中的血凝抑制抗体效价的动态变化;试验二用大肠杆菌油乳苗免疫雏鸡,利用间接血凝法监测血清中大肠杆菌抗体效价的动态变化。分别定期称重捕杀取脾、胸腺、法氏囊,计算免疫器官指数,取肠道内容物计数大肠杆菌和乳酸菌,测定肠道内pH值。结果表明,不同剂量的破壁蜂花粉均能不同程度地提高病毒抗原性抗体效价和菌体抗原性抗体效价,对雏鸡免疫器官的发育以及肠道内环境、菌群的平衡也有一定影响。 相似文献
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Can wild relatives of sorghum provide new sources of resistance or tolerance against Striga species?
Summary The genus Striga contains some of the most noxious parasitic plants, which have a devastating impact on cereal production in Africa; of most importance are Striga hermonthica and Striga asiatica . Complete resistance to infection by Striga species does not exist in cultivated cereals. Of great interest is the possibility that wild relatives of cereals may provide a genetic basis for resistance or tolerance to infection and may be of enormous value for the development of resistant crops. A wild relative of cultivated sorghum, Sorghum arundinaceum , demonstrated tolerance to infection by S. asiatica , with little impact of S. asiatica on host growth or grain production compared with the detrimental impact of the parasite on cultivated sorghum. Infection by S.hermonthica , however, had a significant influence on host performance for both wild and cultivated sorghum. Differences in host:parasite responses may be explained by the timing of parasite attachment and differences in host specificity for these two Striga species. 相似文献