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Jie Zou John L. Snider Honghai Zhu Jiaqi He Yuxia Li Zhiguo Zhou Youhua Wang Yali Meng Binglin Chen Wenqing Zhao Shanshan Wang Wei Hu 《Journal of Agronomy and Crop Science》2023,209(1):94-115
Drought appears at flowering and boll formation for cotton frequently. However, reports on the impact of carbon dynamics in the subtending leaf on boll biomass under periodic droughts are limited. To investigate this, experiments were carried out with two cultivars (drought-tolerant: Dexiamian 1; drought-sensitive: Yuzaomian 9110), three water levels [soil relative water content (SRWC): control (75 ± 5)%, moderate drought (60 ± 5)%, severe drought (45 ± 5)%] and five drought durations (10, 17, 24, 31 and 38 days). A 38-day drought declined the net photosynthetic rate of subtending leaf, which could be collectively attributed to the reduction in carboxylation with reduced ribulose-1,5-bisphosphate carboxylase activity, and stomal limitation with decreased stomatal conductance, along with the damage of photosynthetic apparatus with depressed maximum and actual photochemical quantum yield, leading to lower starch content. A 38-day drought also increased the activities of sucrose phosphate synthase (SPS), sucrose synthase (Susy) and expressions of genes (GhSPS1, GhSPS2, GhSusA and GhSusB) associated with these enzymes, causing the accumulation of sucrose content, finally resulting in lower boll biomass. Some of the above parameters fully recovered under more than 17-day moderate drought or over 10-day severe drought, but boll biomass still decreased after re-watering. Under 10-day moderate drought, all aforementioned indices and boll biomass were completely recovered within 7 days of re-watering, and the recovery capacity of Yuzaomian 9110 was lower than that of Dexiamian 1. Therefore, rapid recovery of photosynthesis and decline in the subtending leaf sucrose content to pre-stress levels are important factors in lessening the impacts of drought on boll biomass and are indicative of cultivar tolerance to short-term moderate water deficit. 相似文献
166.
用由国外引进的IBD变异株鸡胚适应毒经CEF传代适应后所获得的BK912F。毒液进行了病毒理化特性试验和形态学观察,并与标准I型毒CJ801BKF株进行了抗原相关性检测。实验证明,BK91具有IBDV的基本特性且与标准1型毒CJ801BKF株处于不同血清亚型,以2000TCID50/0.2ml的BK912冻干活疫苗免疫SPF鸡后能完全抵抗美国标准弯异株强毒1084A的攻击,一系列试验有BK912仍 相似文献
167.
R. Zhou J. Jia Y. Dong T. Schwarzacher S.M. Reader S. Wu M.D. Gale T.E. Miller 《Euphytica》1998,99(2):85-88
Using the genomic in situ hybridization (GISH) technique, one translocation line, seven translocation-addition lines, five
translocation plus translocation addition lines and two ditelosomic addition lines were identified in backcross progenies
of Triticum aestivum L. -Psathyrostachys juncea (Fisch.) Nevski intergeneric hybrids. No complete P. juncea chromosomes were
detected in the 25 lines studied. The results suggest that intact P. juncea chromosomes may be difficult to isolate in a wheat
background.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
168.
根据气流理论,用仓外与粮堆相通的黑色管道构成循环系统,利用昼夜温差形成慢速环流气流,加速PH3气体在粮堆内的扩散和渗透,达到了较好的杀虫效果。 相似文献
169.
The components of open software system for Electrical Impedance Computed Tomography and their functions under Windows environment are introduced, and the ways to extend system's functions are given. 相似文献
170.
1989年,进行了谷子(Setaria italica)Ch4n×法氏狗尾草位(S.fabeiii)的远缘杂交和杂种胚培养。共接种已授粉子房264个,得到22株苗,仅11株成活。试管苗经继代培养和繁殖,得到了大量的小植株,移栽成活并发育到成熟。经形态学和细胞学鉴定,其中有两个株系是杂种,杂种F_1的染色体数为2n=4x=36,花粉母细胞在减数分裂中期Ⅰ染色体配对不正常,染色体构型为(18-2)Ⅰ+(13-0)Ⅱ+(0-9)Ⅲ+(0-3)Ⅳ,后期染色体分离不正常,形成不正常的四分体和微型小孢子,花粉败育。F_1高度不育,其形态特征介于双亲之间,植株在许多性状上都与父本法氏狗尾草相似,而与母本相差较远。 相似文献