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101.
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   
102.
According to the requirements of the conversion of farmland to forests project (CFFP), we investigated the vegetation factors and environmental factors from more than 6,105 sub-compartments in Liangcheng County, Inner Mongolia by using the Matlab, analytic hierarchy process (AHP), and the hierarchical cluster method (HCM). The site conditions were classified quantitatively. The results show that CFFP at this site comprises five site-type groups and 19 site types. A quantitative site classification system method has been established in this paper. __________ Translated from Journal of Beijing Forestry University, 2005, 27(6) [译自: 北京林业大学学报, 2005, 27(6)]  相似文献   
103.
Abstract. Usual residue-management options are to remove the residue, use it as mulch with or without undercutting or to incorporate it into the soil. While the role of surface mulch in evaporation has been widely studied, the information on the effect on evaporation of mulch with undercutting or residue incorporated into soil, particularly in relation to soil type and evaporativity (Eo) is lacking. We studied the effect of wheat straw used in various ways on the course of evaporation loss from soil columns with three soils at Ludhiana, India and one soil at Bushland, Texas, USA, under two Eo's Energy-limited evaporation rates under mulch (Eom) followed the soil-specific relation Eom/Eo= a e(bRes+cEo), where Res is residue rate t/ha and a, b and c are constants; Eo, is expressed in mm/d. In an effort to model the total evaporation (CE) during the energy-limited stage ‘U’ was obtained from appropriate CE versus time curves and (CE-U) was regressed over (t - ti)0.5 to obtain the slope ‘α’ (Ritchie 1972) for the soil-limited evaporation stage. The observed ‘U’ was independent of mulch rate and Eo but was strongly affected by soil type, Values of ‘α’ decreased with increase in mulch rate and decrease in Eo and coarseness of soil. The otherwise short lived benefit of evaporation reduction with mulch per se, which peaked after a few days was maintained when residue was mixed with soil at the stage when evaporation reduction reached a maximum; this benefit continued for several weeks. Cumulative evaporation values computed from ‘U’ and ‘α’ agreed closely with the observed values under straw mulch for loamy sand and clay loam soils and for ‘undercut’ and ‘residue mixed’ treatments on all soils regardless of Eo, and for all situations under small Eo. However, for sandy loam and silt loam soils under Eo of 10 mm/d, the modified square root of the time function of Jalota et al. (1988) gave a better fit.  相似文献   
104.
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   
105.
A spontaneously occurring rice (Oryza sativa L. ) mutant, characterized by homeotic conversion in glumes and stamens, was found in the progeny of a cross. The mutant showed long glumes and glumaceous lodicules and morphological transformation of stamens into pistils. Mutant florets consisted of 1 to 3 completely developed pistils, some pistilloid stamens with filaments, but tipped by bulged tissue and 0 to 3 stigmas. It seens that the mutant phenotype of the homeotic conversions in glumes and stamens is similar to that of the B loss-of-function mutants in Arabidopsis and Antirrhinum. The mutant is controlled by a single recessive gene as a segregation ratio of 3:1 (wild type to mutant plants) was observed in the F2 generation.  相似文献   
106.
拓扑简化可以为渐进网格带来更好的效果,但目前几乎所有的渐进网格方法都不支持拓扑简化,而且edge collapse和vertex split操作有时会产生非流形.针对这些问题,提出了基于图形旋转系统的渐进网格法.以基于图形旋转系统的数据结构和操作实现了渐进网格,用图形旋转系统的操作集合构建了edge collapse和vertex split操作.在此基础上,通过扩展新操作即可进行任意拓扑变化,从而实现拓扑简化,  相似文献   
107.
108.
禽白血病病毒J亚群(ALV-J)的攻毒试验   总被引:2,自引:1,他引:1  
将禽白血病病毒 J亚群 (AL V- J)内蒙株 NM876 1和 NM9996人工接种于 1日龄爱维茵肉种鸡 ,通过眼观、病理组织学检查观察了攻毒鸡的病理学特征 ;通过 PCR和 EL ISA技术检测了病毒感染率、抗体变化规律以及病毒和抗体的相关性。结果显示 ,攻毒鸡从第 3周开始即可检出病毒 ,NM876 1株和 NM9996株病毒感染率分别为 71.4 %和6 4 .3% ;从第 5周开始 ,出现较明显的病理学变化 ,病变特征以骨髓、肝脏、心脏、脾、卵巢等组织内髓细胞增生为主 ,而法氏囊、脑、坐骨神经无变化 ;攻毒鸡抗体消长变化有一定的规律 ,一般在 7~ 8周龄和 18~ 2 0周龄时分别出现 1次高峰 ,而在 4~ 6周龄、10周龄和 2 3周龄分别出现 1次低谷 ,提示鸡场进行 EL ISA检测时要避开这一时期 ;攻毒鸡产生耐受性病毒血症 ,即病毒阳性而抗体阴性 (V A- )的比例较高 (7/14 ,9/14 )。通过以上的研究证明 ,AL V- J内蒙株疾病模型复制成功 ,NM876 1、NM9996可作为原型株进行相关研究  相似文献   
109.
脱毒桐籽饼(粕)蛋白质及能量营养价值评价   总被引:2,自引:0,他引:2  
选用8头30kg的阉公猪和6只1.7kg的伊莎褐公鸡分别对3种脱毒桐籽饼(粕)Ⅰ、Ⅱ和Ⅲ的蛋白质、氨基酸消化率、代谢率进行了测定。结果表明 :3种脱毒桐饼(粕)Ⅰ、Ⅱ和Ⅲ的蛋白质含量分别为31.17 %、35.12 %和23.98 % ;总氨基酸含量为226.93mg/g、278.38mg/g和178.71mg/g,其中赖氨酸含量4.14mg/g、5.01mg/g和3.47mg/g ,蛋氨酸含量为1.24mg/g、1.33mg/g和0.92mg/g ;能量(GE)为17.72kJ/g、16.42kJ/g 和18.02kJ/g。脱毒桐粕Ⅰ的蛋白质消化率为75.15 % ,消化能为12.85MJ/kg;脱毒桐饼(粕)Ⅰ、Ⅱ的表观代谢能分别为4.88MJ/kg 和6.29MJ/kg,真代谢能为5.53MJ/kg 与6.94MJ/kg。3种脱毒桐饼(粕)的氨基酸之间存在不平衡状况 ,从限制性氨基酸的角度来看 ,脱毒桐饼(粕)的第一限制性氨基酸是蛋氨酸、第二限制性氨基酸为赖氨酸。  相似文献   
110.
优质籼型不育系Q2A的选育   总被引:7,自引:3,他引:4  
Q2A是重庆市农业科学研究所和重庆市种子公司用金23B×中九B的F2代与58B×Ⅱ-32B的F2代杂交,再用复交F2代与珍汕97A杂交引入野败型胞质育成的一个优质籼型三系不育系,2003年7月通过重庆市科学技术委员会组织的技术鉴定.该不育系异交习性好;可恢性好,配合力强;米质优(12项测试指标中有7项达部颁一级优质米标准,5项达二级标准);苗瘟3级,叶瘟3级,颈瘟7级,对苗瘟和叶瘟表现为中抗,颈瘟感病.其与成恢047配组育成的优质杂交中籼新组合Q优5号米质优,产量高,抗稻瘟病,2003年12月通过重庆市农作物品种审定.  相似文献   
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