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排序方式: 共有1306条查询结果,搜索用时 15 毫秒
91.
通过对发酵玉米、发酵高粱秸和发酵麦秸3种秸秆进行发酵处理,添加于饲料中确定其对生长育肥猪的效果。选用48头健康生长状况相似的杜花F1杂种猪,将其随机分为4组,每组12头。第1组作为对照组,饲喂基础日粮;第2、3、4组作为试验组,分别饲喂添加了发酵玉米秸、发酵高粱秸和发酵麦秸的饲料。根据生长育肥猪的采食量、饮水、日常活动、粪便及日增重的效果探讨发酵秸秆的饲喂效果。结果表明,发酵玉米秸喂猪较好,其增重速度与对照组无明显差异。而发酵高粱秸和发酵麦秸效果较差,日增重分别比对照组低11.32%(P0.05)和12.28%(P0.05),每1kg增重耗料分别高于对照组12.20%和13.24%。  相似文献   
92.
Abstract

Studies were conducted to determine the influence of plant growth stage, inoculum density, temperature, and relative humidity (RH) on development of rust (Puccinia pupurea) in sorghum (Sorghum bicolor). Rust development was maximum (>80% severity), when plants of a susceptible sorghum genotype (IS 18420) were inoculated at the four‐ to five‐leaf stage with an inoculum concentration of 4 × 106 urediniospores per ml and incubated at 20–25°C under high RH (>90%) for 24 h. Disease severity (percentage leaf area covered with rust pustules) scores were taken 2 weeks after inoculation. Using this technique, 29 sorghum genotypes were screened for rust resistance in a greenhouse. This technique proved effective In discerning resistant and susceptible genotypes, and IS 3979, ICSH 110, ICSH 86647 and ICSH 871035 were identified resistant (<20% rust severity) compared with a susceptible control IS 18420 (90% rust severity). This technique is simple and rapid, and can be used effectively and economically to screen, on a large scale, germplasm lines and breeding populations in the greenhouse.  相似文献   
93.
高粱抗蚜品种叶片化学物质含量的分析   总被引:2,自引:0,他引:2  
以高粱叶片为试材,对高粱叶片的化学物质进行分析,结果表明:高粱叶片中的可溶性总氮、可溶性糖和游离氨基酸,特别是必需氨基酸,在感蚜品种中的含量显著比抗蚜品种的含量高,且感蚜品种叶液偏酸,抗蚜品种近中性。  相似文献   
94.
孙学保 《中国甜菜》2014,(2):46-47,58
研究了饲用型甜高粱在不同种植模式条件下(全膜双垄沟灌栽培、全膜覆盖平作栽培、露地栽培)对土壤含水量、植株外部形态及产量的影响;单茬收割以及不同株高条件下2茬收割、3茬收割对产量的影响.结果表明:覆膜处理能高效利用降水和灌水,使植株茎秆含糖率增加,显著增加株高和产量,尤其全膜覆盖平作处理较露地栽培水分利用效率高70.52kg/(mm· hm2),增产41.74%.收获两茬产量要比收获1茬高10.98%,比收割3茬高18.64%;在收割两茬的情况下,头茬株高150cm时刈割总产量比头茬株高200cm时刈割总产增产4.49%.在生育期只有150d左右的区域,饲用型甜高粱可选择两茬或单茬收割,头茬在株高150cm左右收割,二茬收割时间在早霜来临之前.  相似文献   
95.
随着黑龙江省对甜高粱这种新兴能源作物的产业研究日益重视与深入,越来越多的细节问题浮出水面。如何发挥黑龙江省的地域优势,排除制约甜高粱产业发展的不利因素,成为种植和推广甜高粱作物的重要课题。就黑龙江省甜高粱产业发展的优势与制约因素进行了分析,并提出了相应的解决办法,为黑龙江省甜高粱产业快速、良性发展提供了理论依据。  相似文献   
96.
A field experiment was conducted during khariff 1984 in sandy clay loam soil under irrigated condition at the Tamil Nadu Agricultural University, Coimbatore, with a view (i) to find out the possibility of introducing short duration dwarf variety of sorghum CO 22 as an intercrop with pigeonpea genotypes, (ii) to study the effect of different plant population levels and intercropping of sorghum CO 22 on pigeonpea genotypes, and (iii) to find out compatible pigeonpea genotypes and plant population level for pigeonpea based intercropping system with sorghum CO 22.
It was observed that increased plant density significantly increased the dry matter production, leaf area index (LAI) and crop growth rate (CGR) during early stages and reduced the net assimilation rate (NAR), relative growth rate (RGR) and CCR during later part of the growth. Intercropping of sorghum CO 22 significantly reduced the dry matter production LAI, CGR, NAR and RGR. Plants in the intercropped stands recorded higher CGR, NAR and RGR during later part of the growth. Among pigeonpea genotypes CO 5 was much affected due to intercropping with sorghum CO 22.  相似文献   
97.
对"丝克高粱"外部形态和营养器官根、叶进行解剖研究及子实的颖片和叶表皮进行扫描电镜观察。结果表明:丝克高粱与"假高粱"营养器官的内部结构非常相似。在理论上丝克高粱有成为危险性有害生物的倾向。研究结果还进一步为正确鉴别假高粱和丝克高粱提供了重要依据。  相似文献   
98.
试验研究了高粱同源四倍体与约翰逊草远缘杂交种及其后代的生物学特性和细胞学行为。结果表明 ,四倍体高粱与约翰逊草种及后代性状的遗传学及细胞学行为较稳定 ,营养体具有强大的杂种优势 ,粮、草量显著高于双亲 ,茎秆具有优良的饲草品质。  相似文献   
99.
The waxy phenotype, associated with endosperm containing little or no amylose, has been recognized in sorghum (Sorghum bicolor L. Moench) since 1933. Although variants of the waxy gene are well characterized in other cereals, the waxy trait has been assumed to be controlled by a single allele, wx, in sorghum. Recent improvements in technologies encourage re-examination of the waxy sorghums. The objectives of this research were therefore to identify and characterize sorghum lines with differing waxy alleles and to describe the actions of those alleles in crosses. Grain of eight waxy sorghum lines (BTxARG1, BTx630, Tx2907, B.9307, 94C274, 94C278, 94C289, 94C369), three wild-type checks (BWheatland, RTx430, BN122), and F2 families from crosses among a subset of these lines were evaluated for presence or absence of granule-bound starch synthase (GBSS), the gene product of the wx locus, and wild-type vs. waxy endosperm. The F2 segregation ratios were tested for fit to a 3:1 ratio using Chi-square analyses. Two distinctly different naturally occurring waxy alleles were identified: One with no GBSS (GBSS−), and one with apparently inactive GBSS present (GBSS+). We propose that the waxy allele with no GBSS be designated wxa, and that waxy allele with apparently inactive GBSS present be designated wxb. These two alleles are located in close proximity on the waxy locus. The wxb allele is dominant to the wxa allele in terms of GBSS production, and both are recessive to the wild-type Wx in terms of amylose content. The U.S. Government's right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.  相似文献   
100.
A study of the inheritance of sorghum resistance to head-bug Eurystylusoldi and midge Stenodiplosis sorghicola has been conducted from anF1-based complete diallel involving four parental lines (namely head-bugresistant Malisor 84-7 & 87W810, and susceptible S 34 & ICSV 197).The trial was conducted at Samanko, Mali, under both natural and artificialhead-bug infestation, in one date of sowing (DOS) in 1995 and two DOSin 1996. Head-bug visual damage scores (under both types of infestation)were indicated and analyzed in all these trials. Head-bug numbers underartificial infestation on the two DOS of 1996, and midge damage scoreunder natural infestation on the second DOS of 1996 were recorded. Allfour parents confirmed their expected level of resistance to head-bugs,while ICSV 197 confirmed its resistance to midge. Diallel analyses showedthat general combining ability (GCA) and thus additive gene effects werevery important in the inheritance of resistance to both pests. Specificcombining ability and maternal effects were generally of minor importance.Mean performance of the parents and their GCA effects were linked, whichsuggests high heritability. Head-bug resistant parents, Malisor 84-7 &87W810, with high per se resistance and negative GCA shouldtherefore be used in breeding for resistance to this pest, while for a similarreason, ICSV 197 should be used in breeding for midge resistance. Resultsconcerning independance between resistance to head-bugs and to midge,are also discussed.  相似文献   
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