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71.
Mungbean (V. radiata) is an important Asiatic legume supplying inexpensive protein to a vast majority of vegetarian masses. To increase markers repertoire in mungbean, a study was conducted to analyse 384 microsatellite markers derived from common bean, scarlet runner bean and adzuki bean for their transferability and polymorphism. The results showed that 87 (24.71%) primer pairs could amplify DNA loci of 20 mungbean genotypes including one accession of V. trilobata, while 52 showed reliable banding and polymorphism. These showed different degrees of variability at each locus producing 250 alleles with the number of alleles varying from 2 to 9. The major allele frequency varied from 0.17 to 0.95, while the polymorphic information content of SSRs ranged between 0.09 and 0.86 with an average of 0.60 ± 0.16. UPGMA revealed three major clusters accommodating ~95% of the accessions while one accession of V. trilobata (‘NSB‐007’) did not group with any other genotype describing the discriminating power of informative microsatellites. This study identified a set of useful microsatellite markers to accelerate the genetic studies and breeding programme of mungbean.  相似文献   
72.
Root length density (LV), mid-day leaf water potential (Ψ leaf) and yield of wheat were studied in 1983 – 1984 and 1984 – 1985 on a Phoolbagh clay loam (Typic Haplaquoll) and on a Beni silty clay loam (Aquic Hapludoll) in the Tarai region of Uttar Pradesh under naturally fluctuating shallow (0.4 – 0.9 m, SWT) and medium-depth (0.8 – 1.3 m, MWT) water table conditions with six water regimes: rainfed (I0); irrigation at cown root initiation (I1); at crown root initiation and milk (I2); at crown root initiation, maximum tillering and milk (I3); at crown root initiation, maximum tillering, flowering and milk (I4); and at crown root initiation, maximum tillering, flowering, milk and dough (I5). Maximum rooting depth (0.8 m under SWT and 1.05 m under MWT conditions) was attained at the dough stage (115 days after sowing, DAS) and was more strongly influenced by fluctuations in water table depth than by the water regime. For wet regimes (I2– I5), roots were concentrated at and above the water table interface and had greater horizontal development, whereas in dry regimens (I0 and I1), due to deficient moisture conditions in the upper soil layer (0.45 m) they invaded lower horizons and had a greater vertical distribution Ψ leaf was not significantly affected by water regime (I1– I5) up to 94 DAS during a wet year (1983 – 1984) and up to 74 DAS during a dry year (1984 – 1985), but was significantly affected thereafter. Grain yields with water regimens I1– I5 during a wet year and for the I2– I5 treatments during a dry year at either water table depth were not significantly different, but there was a (non-significant) trend to lower yield with increasing soil water deficit. Under SWT in I2, the average grain yield wsa 5130 kg ha–1 and under the I3 regime, 5200 kg ha–1. Likewise, under MWT in I3, it was 5188 kg ha–1 and under the I4 regime, 5218 kg ha–1. The results indicate that application of irrigation of more than 120 and 180 mm under SWT and MWT conditions, respectively, did not raise yield. Irrigation given as per schedule I2 under SWT and I3 under MWT conditions in the Tarai situation, appears to be more effective than a very wet regime (I5). Received: 9 December 1997  相似文献   
73.
Cytoplasmic effects on the photosynthesis was investigated in experimentally produced Brassica carinatas of reciprocal cytoplasmic origin. These are obtained by hybridizing B. nigra x B. oleracea var. italica ( B. carinata 226) and B. oleracea x B. nigra ( B. carinata 241). Natural B. carinata and the two parents viz. B. nigra and B. oleracea var. italica were also included in this study. It was observed that the rate of photosynthesis in B. carinata 226 with nigra cytoplasm, and natural B. carinata was higher than that of B. carinata 241 with oleracea cytoplasm. This was substantiated by the diurnal values of photosynthesis among these cultivars. The result indicated that the cytoplasm does affect the rate of photosynthesis in B. carinata and high photosynthetic efficiency in natural B. carinata was due to B. nigra maternal parent.  相似文献   
74.
75.
Grewia optiva Drummond is one of important agroforestry tree species grown by the farmers in the lower and mid-hills of western Himalaya. Different models viz., monomolicular, logistic, gompetz, allometric, rechards, chapman and linear were fitted to the relationship between total biomass and diameter at breast height (DBH) as independent variable. The adjusted R2 values were more than 0.924 for all the seven models implying that all models are apparently equally efficient. Out of the six non-linear models, allometric model (Y = a × DBH b ) fulfils the validation criterion to the best possible extent and is thus considered as best performing. Biomass in different tree components was fitted to allometric models using DBH as explanatory variable, the adjusted R2 for fitted functions varied from 0.872 to 0.965 for different biomass components. The t values for all the components were found non-significant (p > 0.05), thereby indicating that model is valid. Using the developed model, the estimated total biomass varied from 6.62 Mg ha?1 in 4 year to 46.64 Mg ha?1 in 23 year old plantation. MAI in biomass varied from 1.66–2.05 Mg ha?1 yr?1. The total biomass carbon stocks varied from 1.99 Mg ha?1 in 4 year to 15.27 Mg ha?1 in 23 year old plantation. Rate of carbon sequestration varied from 0.63–0.81 Mg ha?1 yr?1. Carbon storage in the soil up to 30 cm soil depth varied from 25.4 to 33.6 Mg ha?1.  相似文献   
76.
Ground water table (g.w.t.) levels were measured twice a month for 2 years in 50 observation wells installed inside and outside the two 18-year-old and 350 m apart plantations of Eucalyptus tereticornis (Mysure gum) at Dhob-Bhali research plot located in Rohtak district of Haryana state (north-west India). Throughout the study, the g.w.t. underneath the plantations remained lower than the g.w.t. in the adjacent fields. The average g.w.t. in the plantations was 4.95 m and the average g.w.t. in the control located in adjacent fields was 4.04 m. Interestingly, the spatial extent of lowering of g.w.t. in the adjacent fields was up to a distance of more than 730 m from the edge of a plantation. Drawdown in the g.w.t. developed due to the effect of a plantation was similar to the cone of depression of a pumping well and the drawdown in the g.w.t. developed due to the joint effect of both the plantations was similar to the combined cone of depression of two pumping wells. There was no correlation between soil salinity and the g.w.t. The fluctuations in g.w.t. caused fluctuations in g.w.t. salinity in the plantation as well as in the adjacent fields, but there was no net increase in g.w.t. salinity underneath the plantation. Sinker roots of Eucalyptus tree reached the zone of capillary fringe up to a depth of 4.40 m, indicating that the Eucalyptus trees were absorbing capillary water of the g.w.t. Thus, in shallow g.w.t. areas of semi-arid regions with alluvial sandy loam soils, the plantations of E. tereticornis act as bio-pumps and therefore, we recommend closely spaced parallel strip plantations of this species for the reclamation of waterlogged areas.  相似文献   
77.
Natural killer cell (NK) receptors for major histocompatibility complex (MHC) class I influence engraftment and graft-versus-tumor effects after allogeneic bone marrow transplantation. We find that SH2-containing inositol phosphatase (SHIP) influences the repertoire of NK receptors. In adult SHIP-/- mice, the NK compartment is dominated by cells that express two inhibitory receptors capable of binding either self or allogeneic MHC ligands. This promiscuous repertoire has significant functional consequences, because SHIP-/- mice fail to reject fully mismatched allogeneic marrow grafts and show enhanced survival after such transplants. Thus, SHIP plays an important role in two processes that limit the success of allogeneic marrow transplantation: graft rejection and graft-versus-host disease.  相似文献   
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