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41.
Feasibility of near-infrared (NIR) spectroscopy for developing multi-species model for plantation timber was explored for estimation of holocellulose in un-extracted milled wood samples. Six commonly planted species of Eucalyptus tereticornis, E. camaldulensis, E. grandis, Leucaena leucocephala, Dalbergia sissoo and Populus deltoides from a wide range of locations and varying age groups were taken for the present study. Few samples of E. hybrid between E. tereticornis and E. camaldulensis were also included in the study to make the model useful for practical application. NIR models were evaluated using partial least squares regression (PLSR-1—full cross-validation, PLSR-2—cross-validation which leaves more than one out) and by dividing the samples into calibration and prediction (test) sets and interchanging them from calibration to prediction sets. The predictive ability of the model was assessed by calculating four ratios of multivariate statistics for individual species model and combined species models. A final combined model for all the species having component range of 76.14–63.03 % and standard deviation of 2.586 % was developed in the spectral range of 7502–4246 cm?1 wave number using 1st derivative plus multiplicative scatter correction using factor of nine by removing samples with outliers found in all the PLSR-2 evaluation steps and in most of the models. The model remained stable even when 30 % of the samples were left out with no outlier detected.  相似文献   
42.
The genetic diversity in genus Prunus is mainly confined to temperate regions of Himalaya and to a lesser extent in the sub-montane and hilly regions of peninsular India. The cultivated and wild species of Prunus have tremendous potential for improvement and utilization. This paper includes the genetic resources of cultivated and wild useful species of Prunus in India with emphasis on their distribution, potential traits/ useful characteristics and utilization. The information on potential genetic resources of Prunus would be helpful in collection, evaluation, conservation and utilization of species.  相似文献   
43.
Aquilaria malaccensis, categorized by IUCN as globally vulnerable, is in high demand in the Middle East and Asian markets for its unique resinous agarwood. In August 2015, symptoms of dieback were observed on A. malaccensis trees planted in the Medicinal and Aromatic Plant Garden, Panbari, Golaghat of the Assam Forest Department. The entire crowns of 70 trees showed complete leaf loss and severe dieback. Rotting at the collar region and of roots was also observed. Isolation from the infected roots consistently yielded Fusarium equiseti identified following standard laboratory procedures and analysis of the internal transcribed spacer (ITS) sequence of the ribosomal DNA. Symptoms of wilt, dieback and root rot were observed on 5‐month‐old Aquilaria seedlings 25 days after inoculation with the isolated fungus. This paper is the first report of F. equiseti causing wilt and dieback of A. malaccensis.  相似文献   
44.
45.
A protocol has been developed for inoculation of rust disease in Dalbergia sissoo using urediniospores of Maravilia achroa. This is the first time that disease symptoms caused by M. achroa were artificially produced. The method has been successfully employed for screening 15 clones of D. sissoo against rust disease. Clone S‐167 was the most resistant remaining free from infection. Clones S‐57, S‐106 and S‐124 were also resistant. Clones S‐19, S‐24 and S‐89 were susceptible.  相似文献   
46.
Farming communities in traditional agroecosystems have been playing an important role in conserving agricultural diversity. They are not only the custodians but also managers of the crop diversity and maintain the dynamic processes of crop evolution and adaptation, the key elements of sustainable agricultural productions. The Himalayan highlands are important centres of crop plant diversity due to high ecological heterogeneity and high local socio-cultural integrations. The crop genetic diversity of Kumaon Himalaya in Uttarachal State of India has been documented in the present study. Existing crop genetic diversity at inter- and intra-species level was assessed and factors for changes in crop compositions and farming systems during the recent past were studied. Farmer management of rice landrace populations were studied in greater detail. Various benefit enhancing options for farmers from local crop diversity were scrutinized based on farmer perceptions and priorities for efficient management of local crop diversity on-farm and its sustainable utilization for agricultural production.  相似文献   
47.
Ziziphus nummularia (Burm. f.) Wight et Arn. is a multipurpose wild economic species well adapted to dry and hot climates of north-western plains, central India and dry regions of peninsular India. This species is reported here for its potential value in drier regions of India and may be considered for future plant genetic resource programmes.  相似文献   
48.
Summary Two hundred genotypes of Coriandrum sativum L. exhibited genetic variation for plant height, primary and effective branches, days to flowering and maturity, umbels and umbellets per plant, grains per umbellet, thousand seed weight, straw yield and grain yield per plant and harvest index. Heritability estimates were high for days to flowering, thousand seed weight and days to maturity; moderate for plant height, straw yield, umbels per plant, umbellets per plant and number of primary branches; and low for harvest index, effective branches, grain yield per plant and grains per umbellet. Phenotypic correlations of grain yield per plant were highly significant and positive with umbellets per plant, umbels per plant, number of effective branches, straw yield per plant, number of primary branches, plant height, number of grains per umbellet and harvest index. Maximum direct contribution to grain yield per plant was made by umbellets per plant, followed by straw yield per plant, umbels per plant and grains per umbellet. Umbellets per plant made sizeable indirect effect via straw yield per plant. Straw yield per plant made sizeable indirect contribution via umbellets per plant.  相似文献   
49.
Resistance to stem rust and leaf rust in five D genome species of wheat viz., 267 accessions of Aegilops tauschii Coss., 39 of Ae. cylindrica Host, 17 of Ae. ventricosa Tausch, 4 of Ae. crassa Boiss. and 8 of Ae. juvenalis (Thell.) Eig were evaluated at adult plant stage. Two hundred and thirty nine (90 %) accessions of Ae. tauschii, 30 (77 %) of Ae. cylindrica, 16 (94 %) of Ae. ventricosa, 3 (75 %) of Ae. crassa Boiss. and 5 (62.5 %) of Ae. juvenalis were resistant to stem rust pathotypes prevalent in South India at Wellington under field condition. Invariably, all the accessions of the five species were resistant to leaf rust pathotypes. Quantitative measurement of disease using area under the disease progress curve revealed the slow progress of disease in the resistant accessions compared to susceptible check (Agra Local). Since all the five species have D genome, it could be concluded that the genes present in D genome might play a vital role in leaf rust resistance, but in case of stem rust resistance wide range of differential response was noticed. Among the species evaluated, Ae. tauschii was exploited to a larger extent, followed by Ae. ventricosa and Ae. cylindrica for leaf and stem rust resistance because of the homology of D genome with hexaploid bread wheat. While, Ae. crassa and Ae. juvenalis could not be utilized so far, possibly due to partial homology which makes the transfer of traits difficult. So, these species have considerable potential as a source of rust resistance and may enhance the existing gene pool of resistance to stem and leaf rusts.  相似文献   
50.
Mineralization and immobilization processes were studied in a soil treated with ammonium sulphate, calcium ammonium nitrate, urea, urea ammonium phosphate or suphala along with unhumified dung. The conversion of fertilizer nitrogen into non-KCI extractable fractions occurred within two weeks and was relatively rapid in the samples treated with urea and urea ammonium phosphate. The mineral nitrogen content during incubation studies was highest in calcium ammonium nitrate treated soils. Amino acid nitrogen appeared to be the main fraction involved in the immobilization and mineralization of nitrogen in soil. Dung behaved as an efficient nitrification inhibitor and slowed the release of nitrogen from fertilizers.  相似文献   
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