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71.
A field experiment was conducted during the winter seasons of 1992–93 and 1993–94 at Anand to study the effect of FYM, nitrogen and source of fertilizer on growth and yield of mustard [ Brassica juncea (L.) Czernj & Cosson]. The results showed significant variation in leaf area index (LAI), crop growth rate (CGR), dry matter production and seed yield. The direct effect of farmyard manure (FYM) was conspicuous in improving the growth of mustard. FYM application at 10 tonnes ha−1 significantly increased the LAI, CGR and dry matter accumulation per plant at almost all the stages during first year study (1992–93) and in pooled analysis. Similarly, nitrogen application registered maximum LAI, CGR at 75 kg level and RGR and NAR at 50 kg level at almost all the during both years. Sulphur carrying source (Ammonium sulphate plus single super phosphate) increased all stages growth characters. Maximum dry matter accumulation per plant and seed yield were recorded with highest levels of FYM (20 tonnes ha−1), N (75 kg ha−1) and source having S. Seed yield was strongly associated with LAI and dry matter accumulation per plant at all the stages.  相似文献   
72.
In a field trial conducted during 1992–93 and 1993–94, the effect of basal (B) nitrogen (N) (45 and 60 kg N ha−1) and foliar application (F) of water (W) or 10 kg N ha−1 and 400 or 600 ppm ethrel (E) (2-Chloro ethyl phosphonic acid) at 70 days after sowing was studied on leaf area index and dry mass at 90 days and pod number per plant, seeds per pod, 1000 seed weight, seed yield, oil content and oil vield at harvest of mustard ( Brassica juncea L. Czern & Coss.) cv. T-59. Recommended basal (B) application of 90 kg N ha (BN90) was used as control. On the basis of 2 year data it was found that basal application of 60 kg N and foliar spray of 10 kg N ha −1 and 600 ppm ethrel gave higher values for growth and yield characteristics and enhanced seed yield and oil yield by 12.5 and 14.8%, respectively over control BN90.  相似文献   
73.
CCC对葡萄试管苗的茎叶生长有显著的抑制作用,茎的高度、节数及节间长度均有明显减少;CCC对生根率没有明显影响,但对插段的生根数量有较大的影响,在一定浓度范围内(20~80mg/L)CCC处理的生根数量有所增加,其中以40mg/L时增加最多,为8.67~8.95条/段。但CCC对根系伸长有明显的抑制作用,随着CCC浓度的升高根长逐渐变短;从干、鲜重的变化来看,CCC处理后墓叶的干、鲜重是随着浓度的升高而减少,但根系的干、鲜重在0~40mg/L范围内呈略增加的趋势,40mg/L以后则大幅度减少。  相似文献   
74.
Three oat (Avena saliva L.) populations (i.e., lines of descent), high grain yield (HG), high protein content (HP), and high protein yield per se (HGP), each developed by three cycles of S, recurrent selection, were evaluated for the effect of selection for groat-protein yield upon other agronomic traits. Selections making up the HG line of descent had high protein yield primarily due to high grain yield, and those selected for HP had high protein yield due to both high protein content and high grain yield. Selection in HGP was on the basis of protein yield per se. Selection caused increases in bundle weight, harvest index, vegetative growth rate, and seed number in all lines of descent. Heading date, plant height, and seed weight were unaffected, whereas groat percentage and test weight were decreased in HP and HGP. Heritabilities were high for heading date, plant height, test weight, and seed weight, moderate for harvest index and bundle weight, and low for groat percentage. Genetic variability generally declined from CO to C3 for all traits. Groat-protein yield and amount of protein per groat increased in all lines of descent. In HG, the increase in groat weight was due primarily to increases in the nonprotein fraction, with groat-protein content actually decreasing. In HGP, groat weight increased due to increases in protein and nonprotein fractions, and groat protein content remained constant. In HP, groat weight and amount of nonprotein per groat decreased, thus increasing groat-protein content. Three cycles of recurrent selection resulted in oat lines with groat-protein yields significantly higher than the highest lines from CO. Utilization of index selection may be desirable to obtain populations of greater breeding value.  相似文献   
75.
近年来,我国的景观植物产业得到了很大发展,但仍存在很多问题,为了解决这些问题,我们开发了景观植物信息查询系统(简称LPIIS)。LPIIS的构建包括后台数据库和管理系统2部分,以Microsoft Access开发后台景观植物数据库,实现各种零散的景观植物数据资料的数字化;采用面向对象的开发语言VB进行信息系统的界面设计和系统集成,实现了人性化的界面,操作更为方便。LPIIS的出现改变了过去景观植物信息管理的手工方式,具有可视化人性化的界面、提供多媒体信息、数据的维护和更新具有继承性、后台数据库可方便的移植于网络等特点。  相似文献   
76.
乳酸菌与中药合生元对肉鸡生长性能及饲料利用率的影响   总被引:3,自引:0,他引:3  
本试验分别向肉仔鸡日粮中添加等量的抗生素和乳酸菌与中药合生元制剂,通过测定肉仔鸡的各项生长指标和饲料利用率指标,探讨乳酸菌与中药合生元在肉鸡生长和饲料利用率方面替代抗生素的优势.结果表明,试验组与对照组在生长性能和饲料利用率上各指标均差异不显著(P〉0.05),说明乳酸菌与中药合生元可以替代抗生素饲喂给肉仔鸡.  相似文献   
77.
甜菜不同种植方式的研究   总被引:2,自引:1,他引:1  
通过试验明确了覆膜移栽纸筒苗栽培方法具有覆盖地膜和育苗移栽双重效应,促进甜菜早发棵,早封垄。提早进入叶丛快速生长期和块根糖分积累期;改善了甜菜光合性能,增加了光合势、净光合率和光合产物经济系数,比不覆膜移栽纸筒苗的增产31%,产糖量增加27.12%,投入产出比大幅度增加。  相似文献   
78.
再论生长的冗余   总被引:29,自引:1,他引:28  
生长冗余概念是由盛承发在1990年首先提出来的。本文从作物个体与群体对立统一关角度出发提出了作物生长冗余的一个解释。盛承发提出的随机波动环境假说可以导致生长冗余的产生;但是,他从物种利益角度出发解释生物进化还有待商榷。本文还综述了黄土高原阗干旱雨养农业地区小麦根系生长冗余问题,并根据前入工作提出适度增加播种深度和苗期叶片刈割等高产栽培措施。  相似文献   
79.
Controlling established horsenettle plants is achieved by suppressing shoot emergence from root systems. The seasonal pattern of shoot emergence and its possible endogenous control in horsenettle ( Solanum carolinense L.) were investigated. The shoot emergence period in an undisturbed population was limited to a seven-week period from mid-April, and a little longer in tilled conditions. Detached roots showed very high shoot-sprouting ability under 15–30°C throughout the year. In shoot clipping experiments, new shoots sprouted only from the stem and not from the root when attached to shoots, whether above-ground or underground. On the contrary, new shoots sprouted from the roots when all parts of the shoots were clipped off. From these results, the limited shoot emergence period in horsenettle is thought to be initiated by temperatures necessary for sprouting and is ended by a growth correlation effect between early emerged and matured shoots.  相似文献   
80.
The effects of root-applied chalcone at 0.15 mmol L−1 on the growth and lignin biosynthesis in maize were investigated. The contents of 4-coumarate: CoA ligase (4CL, EC 6.2.1.12) substrates in maize shoots were increased more rapidly in the samples with chalcone application than in the control and the increase occurred at ≤ 3 h after the application (HAA). The lignin content was reduced by chalcone at ≤ 6 HAA. The shoot growth was suppressed by chalcone at ≤ 9 HAA. Consequently, the results suggest that chalcone suppressed maize growth by inhibiting monolignol biosynthesis.  相似文献   
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