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61.
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   
62.
The aim of this study was to determine the genetics of polymorph systems of Transferrin in Garole sheep breed. The present study was conducted on 95 adult Garole sheep comprising 52 ewes and 43 rams, maintained at Sheep and Goat Breeding Farm of West Bengal University of Animal and Fishery Sciences, West Bengal, during the period from April–September, 2009. The polymorphism of transferrin was determined through SDS-Polyacrylamide gel electrophoresis technique. It was found that the transferrin type was controlled by five codominant alleles (TfA, TfB, TfC TfD and TfE) in Garole sheep. These five alleles, because of co-dominant nature of inheritance, determined the occurrence of nine transferrin genotypes in the analyzed flock. Four (TfAA, TfBB, TfCC and TfDD) of these were homozygous and the remaining five (TfAD, TfBC, TfBD, TfCD and TfDE) heterozygous. It was found that the TfDD genotype (0.263) was predominant while TfDE genotype (0.042) was least common in the analyzed flock. Frequencies of other genotypes were as: TfCD(0.242), TfBD(0.126), TfCC(0.084), TfBB(0.074), TfAA(0.063), TfAD and TfBC (0.053 for each genotype ) in whole population. From the result it was found that in whole population combined, the heterozygotic genotypic frequency (0.516) was more than that of homozygotic genotypic frequency (0.484). Considerable variations were recognized in the frequencies of transferrin alleles. In the whole population frequencies of transferrin alleles were found to be TfA = 0.089, TfB = 0.163, TfC = 0.232, TfD = 0.495 and TfE = 0.021. Transferrin system has shown an absence of genetic equilibrium among the analyzed herd (χ2 value = 51.31). In conclusion, there were polymorphism in Transferrin types and the presence of differences among the frequencies of the five alleles by categories could be a source of genetic variation in Garole sheep.  相似文献   
63.
The objective of this study is to investigate the response of screening, and selection of novel indigenous AM fungal species and Azotobacter chroococcum strains for inoculating apple under different soil disinfestations and moisture conservation mulch practices for sustainable nursery management. Two local AM fungal species namely, Glomus fasciculatum (Thaxter sensu Gerdemann) and Glomus mosseae (Nicol. & Gerd.), and two strains of A. chroococcum viz., A. chroococcum strain-I (AZ1) and A. chroococcum strain-II (AZ2) were inoculated at nursery stage under soil solarization, chemical disinfestation and natural soil conditions at four different mulch materials namely, black plastic mulch (BPM), and organic mulches, i.e. grass mulch (GM); cover crops (CC); green manuring + clean cultivation (Gm + Cc). The comparative performance of the seedlings on the impact of local AM species and A. chroococcum strains on growth characteristics, microbial population, root colonization and leaf nutrient status was evaluated. The inoculation of seedlings to G. fasciculatum and AZ1 increased all growth characteristics (plant height, stem diameter, leaf area and total root length), microbial consortium of the rhizosphere soil and leaf N, P, K and Zn content in all those plots where soil solarization and black plastic mulching was used followed by chemical disinfestations and natural soil conditions at all other mulch types used. These findings suggested that the soil inoculation of G. fasciculatum and AZ1 strain to seeds and/or the saplings under soil solarization with black plastic mulch attained a desirable plant height and become ready for grafting which however saved a period of 1 year for nursery management compared to traditional nursery raising practice, and thus, it may be a viable and feasible approach to maintain soil productivity under nutrient limited soils for sustainable apple nursery production under temperate rain-fed conditions.  相似文献   
64.
Salinity tolerance in garlic cultivars was studied in pots. A 50% yield reduction occurs at 5.60-7.80 dS m1, depending on genotype. It was estimated that if soil salinity exceeds 1.70 dS m_l, the mean garlic yield declined by 1.68% per unit increase in soil salinity.  相似文献   
65.
66.
Pearl millet (Pennisetum glaucum) is cultivated across a wide range of environments ranging from extremely stressful to favourable. The objective of this research was to compare methods to identify productive cultivars for stress and non-stress conditions. Thirty pearl millet cultivars were evaluated at 22 locations that were grouped as stress, non-stress, or intermediate environments. Five selection indices viz., arithmetic mean (AM), geometric mean (GM), AM (standard units), stress susceptibility index (S) and drought response index (DRI) were calculated for each genotype to determine correlation between selection indices and yield under stress (YS), non-stress (YNS), and average conditions (YAV). Both cultivars and locations were significant sources of variation. Phenology of cultivars had different influence on yielding ability in contrasting environments. While earliness was advantageous for stress conditions, cultivars with longer duration tended to yield more under non-stress conditions. YS was only moderately determined by YNS. Both AM and GM were suitable indices for selection of cultivars that would perform well across stress, non-stress, and intermediate environments. Stress susceptibility index (S) was negatively correlated with YS (r=−0.62**) but should only be used as a selection criterion in combination with yield under stress (YS) to identify cultivars adapted to stress environments. DRI was positively correlated with YS but had no association with YNS. Results indicated that DRI might be useful for identifying cultivars with high performance under stress particularly when days to flower differ considerably among test entries.  相似文献   
67.
The opium latex of 1470 individual plant samples of 98 germplasm lines were screened for five major economic alkaloids. The alkaloids profile showed that morphine content ranged from 9.20–20.86% with an average of 15.00 ± 0.267. Codeine ranged from 1.69–6.48% with arithmetic mean of 3.35 ± 0.091, thebaine from 0.52–7.95% with an average of 2.27 ± 0.116. Narcotine ranged from 8.79–17.97% with an average 8.79 ± 0.266 and papaverine content ranged from 0.00–6.07% with an average 1.18 ± 0.167 in over all the germplasm lines. The content of different alkaloids categorized into class interval which exhibited that maximum number of plants and accessions for morphine content fall in group of 10–15% followed by 15–20%, for codeine content in group of 2–4% followed by 4–6%, for thebaine content in 1–2% followed by 2–4%, for narcotine in 5–10% followed by 10–15% and for papaverine content 0–2%. 24 germplasm lines had morphine content above 16.0%. Similarly, 37 germplasm lines for codeine and 13 for thebaine showed consistently high content, i.e., above 3%. 33 germplasm lines had narcotine content above 9% and 20 lines exhibited papaverine content above 2%. Line BR 316 was found unique having thebaine content 6.27–9.33%. The probable reasons of increase or decrease of different alkaloids based on their biosynthetic pathway has been discussed in detail.  相似文献   
68.
A field experiment was conducted for two crop cycles during 2003–2005 and 2004–2006 at Indian Institute of Sugarcane Research, Lucknow to improve bud sprouting, dry matter accumulation (DMA), nutrient uptake and ratoon yield by using potassium fertilizer. Potassium (K) fertigation in standing plant cane increased the number of buds per stubble and number of stalks in ratoon cane. K content of stubble increased by 16.7% with K fertigation. The content of reducing sugars in buds at the time of ratoon initiation improved significantly with K fertigation. It improved dry matter accumulation, number of millable canes, individual cane weight, ratoon cane and sugar yields. Thus, it could be concluded that application of 66 kg K ha?1 with irrigation water in standing plant cane before harvest improved bud sprouting, dry matter accumulation and nutrient uptake in ratoon crop. Irrigation in standing plant cane increased ratoon cane (69.9 t ha?1) and sugar yields (7.6 t ha?1). This increase for ratoon cane and sugar yield was 8.7 and 5.55%, respectively over the control. Further, it increased ratoon cane yield by 15.21% (74.1 t ha?1) and sugar yields by 13.9% (8.2 t ha?1) with K fertigation over the control. Thus, K nutrition holds great promise for improving growth of ratoon cane and sugar yields.  相似文献   
69.
Genetic Resources and Crop Evolution - Balanites roxburghii Planch. is an important medicinal plant of India and used in the treatment of various diseases and disorders. Seeds possess a high amount...  相似文献   
70.
Summary Genetic divergence in 110 population (20 parents and 90 F1 hybrids) of opium poppy was studied by multivariate analysis. All the entries were grouped in 14 clusters. Out of 20 parents, ten were accumulated in one cluster and rest 10 distributed over seven clusters. Estimates of cluster distance showed that maximum intra-cluster distance was in -cluster IX (25.62) followed by cluster I (22.41), V (22.23) and IV (21.06). The inter cluster distances varied from 16.62 (between cluster XII and XIV) to 195.10 (between cluster IV and IX). The cluster analysis indicated substantial diversity among the parental genotypes, which had the potential to release considerable variation in their crosses. The first four principal components (PCs) with eigen values >1 accounted for 68% of variation among the population. The first and second components could account for 29 and 20% of the total morphological and alkaloidal variations, respectively. The PC1 was closely related to yield and yield related traits. The characters contributing greatest positive weight on PC1 were opium yield, plant height, stem diameter, capsule weight/plant and seed yield/plant. The possibilities of relationship between genetic divergence, F1 performance, heterosis and GCA of parents have been explored.  相似文献   
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