障碍型冷害对石河子棉区花铃期棉花生长的影响研究

为了明确棉花主栽品种耐冷性及障碍型冷害的量化指标,达到及时预报,减轻损失的目的。运用智能人工气候箱,在新疆石河子棉区乌兰乌苏农业气象试验站内,于2003-2005年进行低温冷害模拟试验,研究花铃期棉花在经受不同范围和时长的低温后,其植株的受害程度。结果表明,低温处理之后,棉花的叶片、蕾和幼铃都出现异常脱落,经过11.5~18.5℃处理2~4天的其叶片在第8天后才开始异常脱落,其减少率≥35%,并呈持续减少的趋势,而其蕾、幼铃在第6天后就开始异常脱落,减少率≥55%;经过11.5~22.5℃处理2~4天其叶片减少率≤25%,并在处理后的第18~23天基本保持稳定,其蕾、幼铃减少率≥70%。说明花铃期棉花在受冷害之后,其蕾、幼铃先于叶片出现异常脱落,其减少率大于叶片,经过2种相同最低温度不同最高温度的处理,温度日较差小的叶片减少率较高。     

‘Niigata S3’ is a new strawberry cultivar suitable for forcing culture under low temperature and insolation conditions

‘Niigata S3’ is a new strawberry (Fragaria × ananassa Duch.) cultivar that is early flowering and possesses high soluble solid content and good coloration. It was selected from a cross between Kei812 (seed parent) and ‘Asuka-Ruby’ (pollen parent). The first harvest date of ‘Niigata S3’ was December 27, 34 days earlier than ‘Echigohime’ and 9 days earlier than ‘Asuka-Ruby’ (means of 2007 and 2008). The marketable yield of ‘Niigata S3’ was 85% of ‘Echigohime’, 107% of ‘Asuka-Ruby’, while the early yield was 145% of ‘Echigohime’, 85% of ‘Asuka-Ruby’ (based on 2007 and 2008 means). The shape of the fruit is long conical, and its skin color medium-red. The fruit skin hardness of ‘Niigata S3’ was 31.5 g/mm², which was harder than ‘Echigohime’, and its average soluble solid content was 11.4%, which was higher than the values for ‘Echigohime’ and ‘Asuka-Ruby’ (2008). Furthermore, ‘Niigata S3’ did not bear apical overripe fruit. This new cultivar is adaptable to the climatic conditions of Niigata, as well as other regions that experience low winter temperatures and insolation.     

Performance of Three Adelphocoris spp.（Hemiptera： Miridae） on Flowering and Non-flowering Cotton and Alfalfa

The genus Adelphocoris（Hemiptera： Miridae） is a group of key insect pests in cotton fields in China that includes three dominant species： A. suturalis（Jakovlev）, A. lineolatus（Goeze） and A. fasciaticollis（Reuter）. Previous field surveys have found that adults of these Adelphocoris species usually move onto specific host plants when the plants enter the flowering stage. To determine the potential trade-offs for this host-plant preference behavior, the performance of these three Adelphocoris spp. on flowering and non-flowering cotton and alfalfa were compared in the laboratory. The results showed that Adelphocoris spp. had significantly higher nymphal developmental and survival rates, along with increased adult longevity and fecundity on flowering cotton and alfalfa than on non-flowering plants of either species. In addition, compared with cotton plants, alfalfa generally promoted better performance of these three Adelphocoris species, especially for A. lineolatus. Simple correlation analysis indicated that female adult longevity was positively correlated to male adult longevity and female fecundity, and female fecundity was positively correlated to nymphal development and survival rates. This study demonstrated a positive correlation between adult preference and offspring/adult performance for all three Adelphocoris species, with no evidence of any trade-offs for this preference for flowering host plants. These findings support the hypothesis that hemimetabolous insects such as mirid bugs have positive adult preference-adult/nymphal performance relationships, which is likely due to the similar feeding habits and nutritional requirements of adults and nymphs.     

不同生育时期乙烯利处理对花生生物量的影响

为了确定花生生产过程中乙烯利的最佳喷施时期及用量,以湘花2008为材料,通过大田试验研究了盛花期和幼果期分别喷施不同浓度的乙烯利对花生生物量的影响。结果表明:盛花期喷施乙烯利会导致植株提前衰老,不利于生物量的形成;幼果期喷施200~500 mg/L乙烯利,可提高整个生育期花生的叶干重和单株荚果产量,有利于花生生物量的形成。     

膜苞鸢尾的开花特性及繁育系统

为探究膜苞鸢尾(Iris scariosa Willd ex Link.)在自然生境下有性生殖能力和生殖特点,利用原生境和人工栽植地的控制性试验,对其种群的花部特征、传粉媒介、杂交指数(OC,I)、花粉/胚珠比(P/O)等进行研究。结果表明:膜苞鸢尾葶生两朵花,花被片6,内外各3枚,雄蕊短于花柱,与柱头高度相差约2.72 mm,在花朵开放的整个过程中,雄蕊紧贴花柱外侧,雌、雄蕊相对位置不变;杂交指数为4,花粉/胚珠比为1 246,套袋试验表明,其不具备无融合生殖能力,自花授粉不亲和,繁育系统为异交。自然生境下的有性生殖能力受到缺少传粉昆虫的影响。     

短日照诱导对小豆花芽分化的影响

为明确不同短日照诱导对小豆花芽分化的影响,以早熟品种白红2号、中熟品种冀红9218和晚熟品种唐山红小豆为材料,分别设置SD-12 h-1 WK(12 h光/12 h暗处理1周)、SD-12 h-2 WKS(12 h光/12 h暗处理2周)和SD-12 h-3 WKS(12 h光/12 h暗处理3周)3种短日照处理,研究不同短日照对小豆生长、开花特性以及不同部位花芽分化的影响。研究表明,短日照诱导降低3个小豆品种的株高、茎粗、叶面积和地上部干质量,降低程度为唐山红小豆冀红9218白红2号。短日照诱导缩短小豆的生育进程,且诱导时间越长,生育进程加速就越快,同样,小豆的花芽分化进程加快。3个品种相比较:白红2号冀红9218唐山红小豆。不同部位分析发现,顶部花芽发育速度最慢,中部次之,基部较快。以上结果说明,短日照诱导抑制小豆植株生长而促进小豆的花芽分化。     

西藏野生宽叶韭的繁育更新特性研究

【目的】明确西藏野生宽叶韭的繁育更新特性。【方法】通过实地观察,分析宽叶韭的无性繁殖及开花结实特性,测定宽叶韭种子的形态特征、吸水与发芽规律;以温度(4,10,15,17.5,20,22.5,25,30,35,40℃)和贮藏时间(14个月和2个月)为考察因素,研究其对宽叶韭种子发芽率的影响。【结果】(1)西藏野生宽叶韭为冬季倒苗型,可分蘖无性繁殖和种子有性繁殖;(2)开花结实期为8-10月份,平均每花序有小花56.33个,开放授粉下小花结实率98.72%,每小花结籽1~4粒不等,结1粒种子的小花占83.48%,结2粒种子的占15.42%,结3~4粒种子的极少;套袋自交下小花结实率18.35%,每小花有种子1~5粒不等,结1粒种子的小花占73.17%,结2粒种子的占23.78%,结3~5粒种子的极少;(3)种子椭球形,横径1.93mm,纵径3.41mm,百粒质量0.987 7g;(4)在20℃恒温下浸种以4h为宜,最长不超过30h,否则种子内含物大量外渗,可能影响种子发芽;(5)种子常温下贮藏1年以后发芽率急剧下降,短期贮藏(2个月)对发芽率无影响,发芽适温为15~25℃,长期置于10℃下也能达到很好的发芽效果。【结论】西藏野生宽叶韭具有性和无性2种繁殖方式,开放授粉和套袋自交均能结籽,种子发芽适温为15~25℃。     

Can rice cultivar with submergence tolerant quantitative trait locus (SUB1) manage submergence stress better during reproductive stage?

Cultivars with submergence tolerant quantitative trait locus (SUB1) greatly enhance submergence tolerance at vegetative stage. Whether such cultivar is better off or not at reproductive stage submergence is not known. Due to uncertainties in rainfall pattern and delayed monsoon, flooding at later stages corresponding to reproductive stage is very much common now. Therefore, the main goal of the present investigation is to work out the effect of submergence at reproductive stage on yield and yield attributes in three rice cultivars namely Swarna, Swarna-Sub1, and Baliadhan (a traditional rice cultivar showed similar reaction to SUB1). The present study envisages that submergence at reproductive stage greatly decreased the grain yield even though there was no mortality of plants. Yield reduction was greater at flowering stage followed by booting and panicle initiation stage. Swarna-Sub1 performed significantly better compared to Swarna when submergence was given at panicle initiation stage. Swarna-Sub1 and Baliadhan both maintained greater quantities of carbohydrate and total dehydrogenase activity yet the yield reduction was greater in Swarna-Sub1 compared to Baliadhan due to greater chalf formation in the former. The cultivar with SUB1 is quite better off at reproductive stage submergence. Baliadhan is superior to Swarna-Sub1.     

宁夏中部干旱带旱地西瓜根际补灌栽培最佳补灌时期及适宜补灌量的研究

试验对宁夏中部干旱带旱地覆膜西瓜根际补灌栽培技术进行了研究。结果表明:以相同补灌量(5kg/株)在不同生育时期实施1次补灌,以显蕾开花期供水效率和产量最高,分别达1 760.19 kg/(mm.hm2)和40 767kg/hm2;在同一生育时期(显蕾开花期)以不同补水量实施1次补灌,在同时满足供水效率最高和产量最大的前提下,以3 kg/株的补灌量较适宜。在最佳补灌时期实施适量补灌,能够达到节水、增产和高效补偿供水的目的。     

摘心对欧李实生苗生长与成花的影响

为探明摘心对欧李实生苗生长与成花的影响,以当年播种、移植的欧李实生苗为研究对象,分别于苗高20、30、40cm时进行摘心.试验结果表明:欧李实生苗主干摘心能有效地促发二次枝,由于二次枝的产生,极显著地增加了株丛的新梢数量和叶片数量,从而达到了促进欧李实生苗基部的加粗生长、扩大冠幅和当年成花的目的.从3个处理高度的效果来看,以苗高30cm时摘心效果最佳,其二次枝数量、叶片数量、冠幅、苗木基部粗度及花芽分化数量均显著地优于苗高20cm、40cm时的摘心效果.但不同的摘心高度对欧李实生苗的树体高度及叶片的叶绿素含量均未形成显著的影响.