分蘖期干旱处理时间对水稻产量和生理指标的影响

以新两优6号为材料,采用盆栽试验,研究了不同生育阶段干旱胁迫历时对水稻生长、生理指标和产量的影响。结果表明,干旱处理使水稻株高得到抑制,抗倒伏能力提高;使叶片MDA浓度、脯氨酸含量和可溶性糖含量明显增加,随着干旱历时增加,先是急速增加,而后下降;分蘖期短时间干旱胁迫(T1)未造成新两优6号减产,产量反而增加9.2%。     

杂交稻旱秧抛栽秧龄对分蘖及产量的影响

通过对旱秧抛栽不同秧龄分蘖发生及其产量的比较，结果为：（1）对分蘖的发生。单株分蘖总量以秧龄40d为多，有效分蘖数以秧龄35d为多，无效分蘖数以秧龄50d为多。（2）产量比较。秧龄35d的产量最高，秧龄40d的产量次之。综合上述结论可初步认为，旱秧秧龄在35～40d时是大田抛栽适期。     

酸雨胁迫对水稻萌芽及幼苗生长的影响

【目的】酸雨影响农作物的生长发育,探究酸雨胁迫对水稻幼苗萌发期及分蘖期生理指标的影响, 为水稻种植提供理论参考。【方法】采用模拟室内酸雨培养试验,设置 pH 3.5、pH 4.0、pH 4.5、pH 5.0 模拟酸 雨处理与 pH 6.0 对照（CK）,测定不同酸处理后水稻萌芽和生长等相关生理指标。【结果】水稻种子发芽率 （处理后 7 d）随 pH 值降低而下降,但各处理差异不显著。低强度酸雨（pH 4.5、pH 5.0）胁迫水稻种子发芽指 数、幼苗苗长与 CK 差异均不显著,pH 5.0 处理苗长为 6.82（±0.17）cm,略高于 CK（6.78 cm±0.13 cm）;而 高强度酸雨（pH 3.5、pH 4.0）胁迫发芽指数、活力指数和幼苗苗长均显著低于 CK。水稻幼苗株高、根长、叶 绿素在 pH 3.5~6.0 间整体呈现先增后减趋势,弱酸处理部分生理指标优于 CK,其中 pH 4.5、pH 5.0 处理株高分 别为 23.54（±0.97）、24.44（±0.57）cm,均高于 CK（21.54 cm±1.80 cm）;叶绿素含量为 26.13（±1.07） SPAD、27.13（±0.63）SPAD, 均 高 于 CK（23.91±2.00 SPAD）;pH 4.5 处 理 根 长 为 6.56（±0.26）cm, 略 高 于 CK（6.50 cm±0.42 cm）。而强酸处理水稻幼苗各生理指标均显著低于 CK 且增速极为缓慢,表明酸雨对水稻生长 具有明显的“低促高抑”作用。【结论】高强度酸雨胁迫抑制水稻萌发及生长,低浓度酸雨则有一定的刺激作用。     

攀枝花苏铁繁殖初探

对攀枝花苏铁种群自然繁殖习性进行了调查,开展了人工授粉和人工繁殖试验.结果表明:攀枝花苏铁自然种群以根蘖繁殖为主,种子繁殖较少;人工授粉可明显提高种子产量,1年生播种苗保存率可达69%.     

克氏针茅繁殖的生态生物学特性

本文对克氏针茅（StipakryloviiKoshev．）繁殖的生态生物学特性的研究结果表明，在整个生育期内，分蘖的产生有两个峰期（拔节期和果后营养期）．分蘖枝的产生与不定根的形成在幼苗阶段有一定的相关性。当幼苗2月龄时，这是不定根接管种子根大部分作用的关键时期。群落中种子繁殖能力弱的主要原因是土壤紧实，种子入土困难，自然萌发能力低；不定根生长受阻，实生苗成活率低。     

喷施多效唑对水稻秧苗素质及产量的影响

多效唑是一种新型高效植物生长调节剂。本试验采用800、600、400倍液三种浓度，以清水为对照，在水稻1．5叶期、本田分蘖盛期和齐穗期三次喷施。试验结果表明：800、600倍液浓度的多效唑可以提高水稻的秧苗素质和质量。其中以600倍液浓度的多效唑效果最佳；对秧苗株高、总根数、百株茎叶干重及分蘖作用明显，并能提高成穗率、千粒重，显著提高水稻的产量。     

稻茬冬小麦分蘖成穗特性的研究

研究证明：采用主蘖并重是稻茬麦的高产途径。稻茬麦单株利用两个或两个以上的分蘖成穗，即一级分蘖的Ⅰ、Ⅱ及部分Ⅲ或二级分蘖的Ⅰ１及胚芽鞘分蘖等成穗，是可以实现的。每亩基本苗２０～２５万，成穗５０万左右，配以合理的肥水等管理措施，可以实现４５０～５００ｋｇ的产量     

Seed yield related to crop development and to yield components in nine cultivars of perennial ryegrass (Lolium perenne L.)

Summary We had previously found differences for seed yield among nine perennial ryegrass cultivars which were not associated with variation for seed weight. To detect the physiological basis of these genetic differences for seed yield, growth analyses were carried out. We related crop development and components of seed yield to seed yield during three years on clay and sandy soil. No significant differences occurred among cultivars for accumulation and partitioning of dry matter or the pattern of tiller production. Seed yield of the cultivars was not associated with ear number or total dry matter yield of the seed crop. Seed yield was more correlated with the number of seeds per unit area than with seed weight. The number of seeds as calculated after harvest from seed yield and seed weight was much lower than the number of seeds as estimated prior to harvest from seed yield components. The number of spikelets differed significantly among the cultivars, but the ranking was different from that for seed yield. The physiological basis of the genetic differences for seed yield is not clear. Implications for breeding perennial ryegrass are discussed.     

Response of Rice (Oryza sativa L.) Tillering to Sub-ambient Levels of Ultraviolet-B Radiation

The negative impact of enhanced ultraviolet‐B (UV‐B) radiation has been demonstrated for rice, but few studies have examined the effects of low UV‐B radiation on rice growth and physiology. The objective of this study was to determine the effects of low UV‐B radiation on rice physiology with special emphasis on tiller initiation and development in two popular US rice cultivars, ‘Cocodrie’ and ‘Clearfield 161 (CL161)’. Plants received no natural UV‐B radiation because of the UV‐absorption characteristics of the greenhouse glass, hence UV‐B was artificially supplied by supplemental UV‐B lighting. Plants were grown in soil collected from research plots, and were exposed to UV‐B radiation of 0, 4 (sub‐ambient) or 8 kJ m⁻² day⁻¹ (ambient) for 29 days in one experiment and 87 days in a second experiment. ‘Cocodrie’ had no differential response among 0, 4 and 8 kJ m⁻² day⁻¹ UV‐B treatments for all the parameters measured except for plant height, which showed 5% decrease at ambient UV‐B conditions. For ‘CL161’ sub‐ambient UV‐B radiation exposure decreased vegetative tiller production (25%) and total panicle dry weight (15%). The decrease in tiller production was not due to a decrease in carbohydrate content or increase in auxin content under the low UV‐B radiation.     

空间诱变水稻多蘖矮突变体不同分蘖期蛋白质组研究

JB-1返回式卫星搭载水稻(Oryza sativa L.)丙95-503干种子,地面种植后筛选出多蘖矮杆突变体R955.利用荧光差异显示双向电泳(2-D DIGE)对突变体播种后第14天(未发生分蘖)、第21天(分蘖起始)、第55天(最高分蘖期)3个营养生长期叶片总蛋白进行分离及定量分析(未搭载植株为对照),检测到在...