香型水稻叶片香味差异规律研究

以水稻不育系宜香1 A为材料采用B C Sood(1978)介绍的水稻香味快速测定法对香型水稻不同时期叶片香味差异规律进行了研究,结论是,同一叶片中间部分香味更浓,同一单株中主穗与分蘖穗的同位叶片香味无明显差异。在剑叶未完全成熟时,从下位叶至倒2叶香味逐渐变浓,而不完全剑叶的香味不如倒2叶浓;在剑叶完全成熟时,从下位叶至剑叶香味逐渐变浓,在同一单株所有叶片中成熟剑叶香味最浓。     

大蒜叶斑病（Cladosporium allii）的研究Ⅴ．病残体的残存

病残体处于不同相对湿度（ＲＨ）下存活期不同。浸没水中和处于ＲＨ１００％的存活期不超过１个月，ＲＨ９０％的不超过７个月，ＲＨ７５％的不超过１４个月，ＲＨ６５％的不超过３４个月，在ＲＨ５０％～１０％的存活期可达７７个月，即６年半，病残体上休眠分生孢子和菌丝体复苏生长过程是：休眠孢子培养果一大开始萌发。第５天产生孢子梗及孢子。第１２天未见新孢子产生，成熟孢子开给脱落，菌丝萎缩。第６～９天是产生孢子高峰期，一个孢子可新产生孢子１５个，最多达３６个，一个孢子梗可新生孢子４个，最多达６个。     

Response of 14C-Salicylic Acid to Heat Stress After Being Fed to Leaves of Grape Plants

An experiment was conducted to investigate the response of salicylic acid as a second messenger to the heat stress in grape plants. For this purpose, all leaves of grape (Vitis vinifera× V. labrussa L. cv. Jingxiu) plants were removed except the 3rd, 4th, 5th, 6th, and 7th ones. The 5th leaf was fed with 14C-SA, and the 4th and 6th leaves were exposed to high temperature at 40±0.5℃. It was observed that more 14C-SA transported out from the 5th leaf and the distribution of 14C-SA in each organ of plant altered in response to heat stress. The accumulation of 14C-SA in both the 4th and 6th leaves being exposed to high temperature was at least three times higher than that in control. The distribution of 14C-SA in other distal leaves (the 3rd and 7th leaf) decreased, but more 14C-SA accumulated in stems adjacent to the 4th or 6th leaf exposed to high temperature. In addition, there was more 14C-SA being transported upwards or downwards while the 4th and 6th leaves were exposed to high temperature respec tively. Therefore, our results suggested that SA was closely involved in signal transduction of heat stress in grape plants. However, the ratio of 14C radioactivity assayed after SA being extracted to that of direct assay with apparatus was more than 70%, which indicated about 30% 14C was lost or catabolized during transportation.     

雄蚕杂交种的饲养标准技术研究 1.不同温度与叶质对雄蚕稚蚕生理的影响

雄蚕杂交新品种夏华×平 8在春期用不同温度和叶质条件饲养,对其发育情况、龄期经过、稚蚕绝食生命时数和饥饿就眠率、眠蚕体重以及蚕茧产质量进行了调查.结果 1龄期收蚁 24小时用较高温度饲养,其绝食生命时数最长,2、 3龄均以中温饲养表现最好 ; 从饥饿就眠率看,1～ 3龄的总体表现以适熟叶最好 ; 从蚕茧产、质量看,以偏高温度饲养及适熟桑叶为好.     

向日葵叶片动态及功能叶的研究

本文研究了向日葵叶生长动态及功能叶。最初8叶对生,其余轮生。现蕾前叶从茎底部向顶端依次已全部长出,现蕾后到开花阶段则全部展开、扩大,开花期最大叶面积可达1.4m以上。植株呈两头小中间大株型。开花前底部叶片开始黄落,灌浆阶段仅余69％的叶片。生长过程上部邻近的展开叶给新生叶及花盘提供光合产物。主要功能叶层,在花序及开花阶段为植株中部偏上的第19—30叶、灌浆阶段为靠近花盘的第31—39叶,这些叶片的光合强度较大,平均3g/m~2/小时,距花盘越远的叶片功能越小。     

Effects of saline irrigation water and heat waves on potato production in an arid environment

Production of spring potato (Solanum tuberosum L. cv. Désirée) on a deep sandy soil in the central highland of the Negev desert of Israel under drip irrigation with saline water (up to 6.2 dS m⁻¹) was studied in the years 1992–1997. The objective of the study was to determine the effects of saline water irrigation on potato production in an arid environment with special focus on the interactions with weather conditions. Although yields were often high, salinity effects were evident in some years. Thus 1992 and 1996 yields were 6–7 kg m⁻² and showed no significant effect of salinity, while a pronounced drop in yield with increasing salinity was observed in 1993 and 1994. Analysis of weather data for 1993–1994 suggests that the decline in yield was due to interactions between saline irrigation and prolonged heat wave events occurring during crop development. Further experimental work (1997) revealed that tuber yield was most sensitive to combined salt and heat stress when heat waves occurred at 40–60 days after emergence. The combined stress apparently leads to the collapse of mechanisms for avoiding salt accumulation in young expanding leaves, resulting in failure of vegetative growth recovery and a consequent reduction in the leaf area index and canopy functioning. The relationship between tuber sink demand and available photoassimilate supply at certain stages of plant development is discussed with reference to the ability of the potato plant to recover from the combined stress.     

泡桐叶的营养成分及其作饲料的探讨

报道了兰考泡桐和杂交泡桐叶的营养成分,并与其它树种进行比较;探讨了泡桐树叶作饲料的可能性。     

鸭梨不同枝类叶片光合速率在生长期的变化趋势

用改进半叶法测定鸭梨不同部位叶片和不同枝类叶片不同时期的光合速率，结果表明，９年生密植鸭梨外围新梢叶和短枝叶的光合速率分别为１６．７３－３３．７３和１３．５６－２５．７４ｍｇＣＯ２ｄｍ＾－２ｈ＾－１，内膛短枝叶的光合速率为４．５５－９．９０ｍｇＣＯ２ｄｍ＾－２ｈ＾－１。５月下旬至８月下旬的两年连续测定表明，盛果期大树外围新梢叶的光合速率高于外围短枝叶。短枝叶的光合速率在５月份呈现最高值。６月份及以     

水稻叶片衰老生理的研究进展

总结了近年有关水稻叶片衰老生理的研究进展,包括水稻叶片衰老的生理机制,衡量水稻叶片衰老的常用生理生化指标及其变化以及水稻叶片衰老调节等研究成果,进而对今后水稻叶片衰老研究中着重应解决的一些问题进行了讨论。     

水稻品种产生纹枯病菌核能力的研究

通过三年试验,舒城县农科所1987、1988和1989年参试早稻品种分别是10个、10个和13个,各年每公顷产生纹枯病菌核数量最多的品种分别为最少品种的2.4倍、19.4倍和2.2倍.合肥省农科院植保所1987、1988和1989年参试中稻品种分别是14个、10个和13个,各年每公顷产生菌核数量最多的品种依次为最少品种的2.9倍、5.5倍和4.6倍.这表明无论早稻或中稻品种间产生菌核的数量十分悬殊.虽然同一品种在同块田中产生菌核的能力在年度间变化较大,但有些品种如83-15-1-17-3产生菌核数量总是较少,而有些品种如庆莲3号产生菌核总是较多.因此,通过种植产生菌核少的品种,就有可能找到一个减少土壤中菌核数量的积累来压缩初次侵染源和预测病情的新途径.