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61.
Seshadri Shivashankar Manoharan Sumathi Vala Keshava Rao 《The Journal of Horticultural Science and Biotechnology》2017,92(2):113-119
Uneven ripening (UR) is a physiological disorder of unknown origin in ‘Bangalore blue’ grape (Vitis vinifera × Vitis labrusca) leading to wine of inferior quality. A preliminary study found wide variations in total dehydrogenase activity (TDH) of seeds from unevenly ripe berries. In our experiments, gibberellin (GA3) applied to young grapes increased seed TDH activity and reduced the incidence of uneven ripening to 2% compared with 35% in the control. In contrast, paclobutrazol (PBZ) decreased TDH activity and increased the incidence of the disorder to 58%. GA3-treated berries had higher concentrations of sucrose and TDH activity in seed representing mature seeds with high viability. In contrast, PBZ-treated and control berries had higher concentrations of glucose and lower TDH activity, indicating immature seeds with low viability. These results suggested that competition among developing berries can lead to differences in seed gibberellin content, seed viability and the rate of berry growth resulting in green, purple, and black berries at harvest. The study established the role of seed viability in uneven ripening and demonstrated that the incidence of the disorder is reduced by the application of GA3 to immature berries. 相似文献
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63.
Jawahar Lal Katara Ram Lakhan Verma Debkanta Nayak Umakanta Ngangkham Soham Ray Hatanath Subudhi Lambodar Behera Sanghamitra Samantaray Ravi Nageswara Rao Onkar Nath Singh Trilochan Mohapatra 《Plant Breeding》2017,136(1):74-82
Identification of new parental lines is crucial for developing ecology‐specific hybrids with ideal agronomic performance. We screened a total of 570 different ecology‐specific Indian rice varieties for the presence of fertility restorer genes, Rf3 and Rf4 using tightly linked markers DRRM Rf3‐10 and RM6100, respectively. Among these varieties, 13% carried Rf3Rf3/Rf4Rf4, 31% carried rf3rf3/rf4rf4, 6% carried Rf3Rf3/rf4rf4 and remaining 50% carried Rf4Rf4/rf3rf3 allelic combinations. A mini set of 40 varieties with variable allelic combinations of fertility restorer genes were testcrossed with WA and Kalinga‐based CMS lines. All the 80 F1s were evaluated for spikelet fertility and fertility restoration ability. Rf3Rf3/rf4rf4 genotypes mostly behaved as partial maintainers or partial restorers. In contrast, rf3rf3/Rf4Rf4 genotypes were partial or effective restorers. However, double dominant genotypes showed better fertility restoration than the genotypes containing Rf3 or Rf4 individually. Some of the genotypes showed unexpected restoration pattern implying occurrence of other fertility restorer(s) apart from Rf3 and Rf4. The perfect restorers and maintainers identified in this study can be directly used in hybrid rice breeding. 相似文献
64.
Agronomic traits of soybean cultivars released in different decades after grafting record‐yield cultivar as rootstock
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Shengyou Li Fei Teng Demin Rao Xingdong Yao Huijun Zhang Haiying Wang Shuhong Song Steven K. St. Martin Futi Xie 《Plant Breeding》2017,136(2):133-138
Breeders have seldom considered the selection for root traits during the genetic improvement in soybean. It is hypothesized that grain yield would be increased by the root function improvement, especially for the current cultivars. The objective of this grafting experiment was to determine the effect of record‐yield cultivars L14 or Z35 as rootstocks on agronomic traits of cultivars released in different decades. A total of 11 cultivars, released in different decades, were used to graft onto L14 or Z35 rootstocks. The agronomic traits were measured in the pot‐culture experiments. Grafting cultivars released in different decades onto L14 or Z35 rootstocks resulted in higher yield, 100‐seed mass and apparent harvest index as compared with those of non‐grafted or self‐grafted plants. Grain yield gain of cultivars grafted onto record‐yield cultivar rootstocks was 0.40 g/plant/year from 1966 to 2006, which was larger than that of non‐grafts and self‐grafts (0.27 g/plant/year). The yield of current cultivars should increase more if their root functions were improved. 相似文献
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Arsenic (As), one of the most harmful toxicant at the global level, severely affects plant metabolism when taken up. Interestingly, the presence of silicon (Si) as a fertilizer in As-contaminated soil is an effective strategy to decrease As accumulation in plants. Brassica juncea (var. Varuna) were grown hydroponically to investigate the role of Si at biochemical and molecular levels under arsenite (As3+) stress. Seedlings of B. juncea were exposed to As3+, Si, and a combination of both elements. Our data demonstrated that seedlings exposed to As3+ showed an inhibition in shoot length, chlorophyll, carotenoid, and protein, while co-application of Si improved these growth parameters. Silicon supplementation reduced As accumulation in shoot. Increase/decrease was observed in stress-related parameters (cysteine and proline), antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, and catalase), and oxidative stress markers (malondialdehyde and H2O2), which were improved upon co-application of Si as compared to As3+ alone treatment. Random amplified polymorphic DNA (RAPD) is a suitable biomarker assay for plants for assessing the genotoxicity. Seven RAPD primers produced a total of 39 and 48 bands in the leaves of the untreated and treated seedlings, respectively. The RAPD band-profiles and genomic template stability were consistent with other growth and physiological parameters. In conclusion, the genotoxic alterations along with the biochemical parameters indicate that the exposure to Si mitigates As3+-induced oxidative stress by improving the stress-related parameters and antioxidant system in B. juncea. 相似文献
67.
Fahd M. Abdelkarem Mohamed E. Abouelela Mohamed R. Kamel Alaa M. Nafady Ahmed E. Allam Iman A. M. Abdel-Rahman Ahmad Almatroudi Faris Alrumaihi Khaled S. Allemailem Hamdy K. Assaf 《Marine drugs》2022,20(2)
Gorgostane steroids are isolated from marine organisms and consist of 30 carbon atoms with a characteristic cyclopropane moiety. From the pioneering results to the end of 2021, isolation, biosynthesis, and structural elucidation using 13C-NMR will be used. Overall, 75 compounds are categorized into five major groups: gorgost-5-ene, 5,6-epoxygorgostane, 5,6-dihydroxygorgostane, 9,11-secogorgostane, and 23-demethylgorgostane, in addition to miscellaneous gorgostane. The structural diversity, selectivity for marine organisms, and biological effects of gorgostane steroids have generated considerable interest in the field of drug discovery research. 相似文献
68.
Four wheat (Triticum aestivum L.) cultivars 711, PBW343, 3765 and WH542 were screened for studying variations in glycinebetaine (GB) content and plant dry mass under 100 mmol L-1 NaCl stress. A tolerance index was calculated using plant dry mass data to select salt-tolerant and salt-sensitive types and find association between tolerance index and GB content. Tolerance index has been used as a good criterion to select the tolerant types under high salinity stress. Further, physiological differences in salt-tolerant cultivar 711 and salt-sensitive cultivar WH542 were examined. The salt-tolerant cultivar exhibited greater GB content, which was found correlative with ethylene. The cultivar also showed higher nitrogen (N) content and nitrate reductase activity, reduced glutathione and higher redox state resulting in maximal protection of plant dry mass than the salt-sensitive type. Thus, the content of GB may be considered as important physiological criteria for selecting salt-tolerant wheat types. 相似文献
69.
基于迁移学习的葡萄叶片病害识别及移动端应用 总被引:7,自引:6,他引:1
为解决已有的卷积神经网络在小样本葡萄病害叶片识别的问题中出现的收敛速度慢,易产生过拟合现象等问题,提出了一种葡萄叶片病害识别模型(Grape-VGG-16,GV),并针对该模型提出基于迁移学习的模型训练方式。将VGG-16网络在ImageNet图像数据集上学习的知识迁移到本模型中,并设计全新的全连接层。对收集到的葡萄叶片图像使用数据增强技术扩充数据集。基于扩充前后的数据集,对全新学习、训练全连接层的迁移学习、训练最后一个卷积层和全连接层的迁移学习3种学习方式进行了试验。试验结果表明,1)迁移学习的2种训练方式相比于全新学习准确率增加了10~13个百分点,并在仅训练25轮达到收敛,该方法有效提升了模型分类性能,缩短模型的收敛时间;2)数据扩充有助于增加数据的多样性,并随着训练次数的增加,训练与测试准确率同步上升,有效缓解了过拟合现象。在迁移学习结合数据扩充的方式下,所构建的葡萄叶片病害识别模型(GV)对葡萄叶片病害的识别准确率能达到96.48%,对健康叶、褐斑病、轮斑病和黑腐病的识别准确率分别达到98.04%、98.04%、95.83%和94.00%。最后,将最终的研究模型部署到移动端,实现了田间葡萄叶片病害的智能检测,为葡萄病害的智能诊断提供参考。 相似文献
70.
以凤尾兰(YuccagloriosaLinnaeus)的茎尖、幼嫩茎段及嫩叶为外植体进行组织培养。结果表明以嫩叶为外植体的愈伤组织诱导率最高,由茎段诱导的愈伤组织继代增殖最好,由茎尖诱导的愈伤组织诱导不定芽表现最佳。筛选出最佳初代培养基MS 6-BA3.0mg/L NAA0.2mg/L;愈伤组织增殖培养基MS 6-BA8.0mg/L NAA0.1mg/L;不定芽诱导培养基为MS 6-BA5.0mg/L KT1.0mg/L;不定芽增殖培养基为MS 6-BA4.0mg/L NAA0.05mg/L 椰子水100mL/L;生根培养基为1/2MS NAA0.2mg/L。 相似文献