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51.
Fertility restoration of CMS-based hybrids is an integral part of breeding hybrids and the development of new hybrid parents with desirable agronomic and market preferred traits on regular intervals is essential for sustainability of such programs. This paper reports identification of 25 male-sterility maintainers and 179 fertility restorers of A4 cytoplasm in pigeonpea (Cajanus cajan (L.) Millsp.). Multi-location evaluation of hybrids exhibited high stability for fertility restoration across diverse environments. The diversity study showed a large variation for important traits both at phenotypic as well as genetic levels. The potential use of this information in hybrid pigeonpea breeding has been discussed.  相似文献   
52.
The Western Himalayan region of India possesses rich genetic diversity of rice (Oryza sativa L.). Rice landraces having withstood the rigors of biotic and abiotic stresses, suit to the local conditions of farms and reflect socio-cultural preferences can still be found in crop fields located distantly in rural and tribal areas. This region is known for growing World fame basmati in the foot hills and many varieties of red rices grown at higher elevations, known for cold tolerance and medicinal properties. Genetic resources of rice were collected for about 8 years (1999–2006) and 1069 germplasm accessions including 154 named landraces were collected. Prominent landraces such as Begumi, Ramjwain, Thapachini, Naurang, Hansraj, Tilakchandan, Lalsati, Jhini, Mushakbudji, Jattoo, Barpasso, Qadirbeigh, Safedbrez, Shahie known for their special quality attributes were collected. The change in land use, cropping patterns and aggressive introduction of modern varieties in the region has resulted in the loss of a large number of landraces especially from irrigated lands. The present paper looks at the status of rice genetic resources, genetic variability, genetic erosion and future strategies to conserve rice germplasm on farm and to maximize its use in rice breeding.  相似文献   
53.
用10年生丛生竹的节片通过离体腋笋增殖和生根产生出府竹小苗。不同季节对无菌培养物的建立、腋芽发萌和初代培养的影响很大。3片丛生林中,无菌培养物的建立有差别,但腋芽发萌没有差别。用加有31.06uM BA和2.85um IAA的MS液体介质,最大的增值率为3.18;用加有20~25um IBA MS液体介质,离体生根率为66.7~77.8%。用不同的植物生长素,生根所用的天数也不同,而IBA液能在短期促进生根,仅仅为2-3周。成功炼苗后,在装有土壤、沙子和农家肥塑料袋里,离体繁殖的小苗成活率为90%,大约有2000株小苗用于野外栽植。  相似文献   
54.
Soil phosphorous (P) deficiency is a major constraint to plant production which is overcome by adding inorganic-phosphate as chemical fertilizers. Fluorescent pseudomonads are the diverse group of bacteria able to mobilize sparingly soluble phosphate form. Total three hundred seven fluorescent Pseudomonas isolates were obtained from the Aloe barbadensis (Miller) rhizosphere. These Pseudomonas strains were further evaluated in vitro for their ability to solubilize phosphate and to produce indole acetic acid (IAA), hydrogen cyanide (HCN), siderophore and 1-aminocyclopropane 1- carboxylate (ACC) deaminase. Fifty three (36.8%) isolates produced IAA and 52 (36.1%) isolates produced siderophores whereas 36 (25.0%) and 31 (21.5%) isolates produced HCN and ACC deaminase, respectively. A positive correlation existed between siderophore and ACC deaminase producers. Cluster analysis showed rhizosphere as the major factor influencing the ecological distribution and physiological characterization of phosphate solubilizing bacteria (PSB). Based on partial 16S rRNA gene sequencing PSB were identified as Pseudomonas putida, Pseudomonas sp. and Pseudomonas plecoglossicida with highest phosphate solubilization ability. In conclusion, these phosphate solubilizing fluorescent pseudomonads would help in understanding their role in phosphorus solubilization and identification of potent phosphorus solubilizers from the rhizosphere of commercially grown A. barbadensis.  相似文献   
55.
The study aimed to investigate the effect of feed supplements, viz Lactobacillus plantarum LGFCP4 (laboratory isolate from GIT of Guinea fowl), Lactobacillus acidophilus (NCDC, Karnal) and in‐feed antibiotic bacitracin methylene disalicylate (BMD) on growth performance, FCR, carcass traits and immune organs weight, intestinal histomorphometry and gastrointestinal microflora population in broiler chickens. In a completely randomized design, CARIBRO‐Dhanraja broiler chicks (n = 160) were used with four treatment groups. During the entire experimental duration of 35 days, treatment groups were provided with different dietary treatments (T1 – basal diet (negative control), T2 – antibiotic growth promoter BMD 20 g/100 kg feed (positive control), T3 – 1 × 10cfu of L. acidophilus/gm‐fermented feed +MOS 1 g/kg feed and T4 – 1 × 10cfu of laboratory‐isolated L. plantarum LGFCP4/gm‐fermented feed+ MOS 1 g/kg feed. After 35 days of experimental period, no significant results have been observed in different growth performance traits among treatment groups. Cut‐up parts and edible organs' weight remained unaffected by dietary supplementation, whereas weight of immune organs were significantly higher (p < 0.05) in L. plantarum LGFCP4‐supplemented group. At the end of feeding trial, significantly (p < 0.05) lower E. coli count was observed in crop of T4 birds, while in ileum, T2 and T3 showed lower count. In caeca, T2 group showed lowest E. coli count. Salmonella count in crop and ileum was significantly (p < 0.05) low in T3 and T4, while in caeca, T2 group showed lowest count. In terms of histomorphometry, duodenal villous height (VH), crypt depth (CD) and VH:CD ratio were higher for T3 and T4 and lowest values were obtained for T2 group. The results of the study showed that L. plantarum LGFCP4 isolated from GIT of guinea fowl can effectively replace in‐feed antibiotic growth promoters in broiler diets by altering intestinal villi morphology and improving the gut health by reducing the pathogenic microbial load.  相似文献   
56.
Water contamination has reached an alarming state due to industrialization and urbanization and has become a worldwide issue. Dyes contaminate water and are addressed extensively by researchers. Various technologies and materials have been developed for the treatment of contaminated water. Among them, adsorption has attracted great attention due to its ease and cost-effective nature. In recent years, graphene-based composites have shown great potential for the removal of contaminants from water. The literature reveals the usefulness of composites of graphene with metal oxides, carbon derivatives, metal hybrids and polymers for the removal of organic dyes from contaminated water. In this review, efforts have been made to compile the studies on the removal of cationic and anionic dyes from water using graphene-based composites.  相似文献   
57.
It is globally accepted that soil carbon (C) dynamics are at the core of interlinked environmental problems,deteriorating soil quality and changing climate.Its management remains a complex enigma for the scientific community due to its intricate relationship with soil nitrogen (N) availability and moisture-temperature interactions.This article reviews the management aspects of soil C dynamics in light of recent advances,particularly in relation to the availability of inorganic N pools and associated microbial processes under changing climate.Globally,drastic alterations in soil C dynamics under changing land use and management practices have been primarily attributed to the variation in soil N availability,resulting in a higher decomposition rate and a considerable decline in soil organic C (SOC) levels due to increased soil CO2 emissions,degraded soil quality,and increased atmospheric CO2 concentrations,leading to climate warming.Predicted climate warming is proposed to enhance SOC decomposition,which may further increase soil N availability,leading to higher soil CO2 efflux.However,a literature survey revealed that soil may also act as a potential C sink,if we could manage soil inorganic N pools and link microbial processes properly.Studies also indicated that the relative,rather than the absolute,availability of inorganic N pools might be of key importance under changing climate,as these N pools are variably affected by moisture-temperature interactions,and they have variable impacts on SOC turnover.Therefore,multi-factorial studies are required to understand how the relative availability of inorganic N pools and associated microbial processes may determine SOC dynamics for improved soil C management.  相似文献   
58.
For commercial development of hybrids the four pre-requisites are; availability of perfect male-sterility system, efficient mass pollen transfer mechanism, hybrid vigor, and the large scale seed production of hybrids for commercialization. The type of male-sterility governs the acceptance of hybrids by farmers. Genetic male-sterility (GMS) system was not accepted by farmers due to the economics of large scale seed production. The major drawback was rouging of fertile counterpart from the female plot, which was time consuming and labor intensive. Cytoplasmic-genic male-sterility (CMS) system usually was a better option for large scale seed production. Hybrid vigor has been utilized in some cereal and vegetable crops. Pigeonpea (Cajanus cajan) displays considerable natural out-crossing and now CMS lines are available with different cytoplasmic backgrounds. This mini-review reports the research on development of CMS lines and CMS-based hybrids in pigeonpea.  相似文献   
59.
酶在动物饲料中的应用已有多年的历史,并已证明能帮助家禽取得良好的生产性能。本文作者将讨论酶在家禽营养中的相关事实和数值,以及其被添加入玉米的哪些替代饲料中是有效的。  相似文献   
60.
木豆胞质雄性不育系柱头活力研究   总被引:2,自引:1,他引:1  
在中国南部地区南宁市(位于北纬22°49′、东经107°45′)大田生产条件下对2个木豆胞质雄性不育系ICPA 2039和ICPA 2043花期柱头活力进行研究,发现柱头活力始于开花前2d并维持至开花后4d,活力峰值出现在开花当日;人工授粉成荚率ICPA 2039和ICPA 2043分别为84.0 %和82.0 %;柱头活力期可通过花冠/花萼长度比来判定,ICPA 2039和ICPA 2043分别为2.75±0.075和2.60±0.283.柱头活力周期越长,获得虫媒授粉的异交机会越多,因此柱头活力周期是杂交育种成功率的一个重要技术参数,长的活力周期也是种子生产获得高产的保证.  相似文献   
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