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31.
Chlorophyll (Chl) and nitrogen (N) status of leaves provide valuable information about the physiological condition of plants. The conventional methods for measuring Chl and N contents in leaves are destructive, costly, time-consuming, and do not allow repetitive measurement of the same sample. The Damask Rose (Rosa damascena Mill) is an important aromatic crop in the western Himalaya region in India. Generally, flower yield and oil yield of the Damask rose are correlated with nitrogen, phosphorus, and potassium (NPK) levels in the leaf at the bud development stage. The dynamics of N within the rose plant have not been reported clearly. Thus, there is a pressing need for non-destructive techniques to estimate Chl and N content in the leaf of the Damask rose. Our objective was to establish an appropriate mathematical relationship between the Chl content index (CCI) value and the total Chl/N contents for non-destructive estimation of total Chl and N in the leaf of the Damask rose. The regression models were developed with destructively measured parameters (total Chl and N) as the dependent variable and a parameter derived from CCM-200 as the independent variable (CCI). We found that polynomial regression models are suitable for non-destructive estimation of total Chl, and the model predicted values were very close to traditionally measured values with a root mean square prediction error (RMSEp) less than 0.20?mg?g?1 of Chl. In the case of N estimation, a power regression model was appropriate with lowest Akaike's information criteria (AIC) and root mean square validated error (RMSEv) value. Significant correlations (P?≤?0.001) were observed between traditionally measured values and our model predicted values in both cases.  相似文献   
32.
Genetic improvement of sugar content in sugarcane would benefit from the availability of sufficient DNA markers and a genetic map. Genetic linkage maps were constructed to identify quantitative trait loci (QTLs) for seedling brix (SB), brix (B), sucrose percent in juice (SUC), stalk number (SN), stalk length (SL), stalk diameter (SD), internodes (INT), number of green leaves (NGL), at three crop cycles across seven environments in a segregating population with 207 individuals derived from a bi-parental cross of sugarcane elite cultivars. Linkage analysis led to the construction of eight linkage groups (LGs) for Co86011 and sixteen LGs for CoH70. The combined length of the two linkage maps was 2606.77 cM distributed over 24 LGs. 31 QTLs were identified: 2 for SB, 7 for B, 6 for SUC, 4 for SN, 1 for SL, 3 for SD, 6 for INT and 2 for NGL at LOD scores ranging from 2.69 to 4.75. 7 QTLs (22 %) had stable effect across crop year and locations. Markers from parents were found to be associated with both positive and negative effect on all of the traits analyzed. The most important QTLs intervals identified in this study using single-dose marker, were qB2, qSUC2, qINT2 and qB2, qSUC2, qSL2, qINT2 located between SSR markers UGSM31548 and UGSM31649. These QTLs could be put into use in marker assisted breeding.  相似文献   
33.
Salinity is a major constraint affecting rice productivity in rainfed and irrigated agro-ecosystems. Understanding salinity effects on rice production at the reproductive stage could improve adaptation for this trait. Identifying quantitative trait loci (QTLs) controlling adaptation to salinity may also accelerate breeding rice germplasm for environments prone to this stress. We used the salt tolerant landrace ‘Hasawi’ as a donor parent to generate three F2 offspring (consisting each of 500 individuals) with three African cultivars (‘NERICA-L-19’, ‘Sahel 108’ and ‘BG90-2’) used as recipient parents (RP). The F2s and F2:3s were evaluated for grain yield and other traits in saline fields. Salinity caused reduction in all measured traits across the F2-derived offspring, e.g. grain yield reduced between 65 and 73 %, but some offspring had twice the RP’s grain yield. QTL analysis revealed 75 QTLs for different traits in all 3 genetic backgrounds (GBs): 24 of them were common among all the 3 GBs while 31 were noted in 2 GBs, and 17 in one GB. ‘Hasawi’ contributed on average 49 % alleles to these QTLs. Two yield and yield related QTLs (qGY11 and qTN11) common in all 3 GBs were mapped on the same chromosomal segment suggesting these QTLs might be stable across different GBs. Four other QTLs were strongly associated with salinity tolerance with peak marker RM419, representing a potential candidate for MAS due to high LOD score and relatively large effect QTLs.  相似文献   
34.
证据显示印度喜马偕尔北部的喜马拉雅州森林生物量大量减少。政府通过局部测定核查了森林生物量减少情况。本文以树木生物量来衡量森林退化,评估了主要用地类型内森林生物量的现状,检查了森林可持续性。结果表明,保育林分树木地上部最大生物量平均为1158t·hm-2,保护林、休耕地、耕作非灌溉地、草地、果园和耕地灌溉地的平均生物量依次是728,13,11,8,5和3t·hm-2。当地农民用于烧柴、马料或其他用途的树木生物量仅占可获得的生物总量的0.31%。现在的取用水平只能在短期内维持森林可持续性,从长期来看森林再生不足。采用对数生长模型对未来30年的森林生物量进行料模拟,并通过敏感性分析对影响系统行为的输入变量的相对显著性进行了分析。拟合模型强调了未来的森林资源降低不可避免。政府部门应该积极响应,出台相应政策才能有效地保护森林资源。  相似文献   
35.
Tropical Animal Health and Production - Heat shock proteins (HSPs) act as molecular chaperones which are preferentially transcribed in response to severe perturbations of the cellular homeostasis...  相似文献   
36.
37.
Pigeonpea is an important food legume of the semi-arid tropics grown mainly under subsistence agriculture. As a first step to address the five decades-long yield stagnation, a proof-of-concept for a commercially viable CMS-based hybrid technology with high standard heterosis and fertility restoration has been demonstrated. Six generations of backcrossing and selection for male sterility, and agronomic superiority using a Cajanus cajanifolius- (A4 cytoplasm) based CMS donor (ICPA 2039) and a medium-maturity group recurrent parent ICPL 20176 (ICPB 2043) which resulted in a stable male sterile line (ICPA 2043) with near-perfect male sterility and superior agronomic traits. Following backcrossing and selections, the A-line (ICPA 2043) appeared to be morphologically similar in terms of various qualitative and quantitative traits compared to the B-line (ICPB 2043). However, differences between ICPA 2043 and ICPB 2043 were observed for days to maturity, 100-seed weight, pods plant-1, and seed weight plant-1. These differences may not be genetic but physiological. The best heterotic restorer line selected in a cross (ICPH 2671) combination restored a mean of 96.49% male fertility in 36 environments (12 locations, 3 years). Present investigation did not reveal significant G×E interaction for fertility restoration, indicating the possibility of obtaining high and stable grain yields in the pigeonpea growing areas of South and Central India.  相似文献   
38.

The effect of rumen-protected nutrients (bypass fat, BPF; bypass protein, BPP; or their combination, BPPF) was investigated in Murrah buffaloes during the early stage of lactation. Forty Murrah buffaloes (BW 531.92?±?10.85 kg) just after parturition were randomly distributed into four groups according to parity and milk production. Buffaloes individually fed ration from day 0 to 90 postpartum according to feeding group and nutrient requirement. Control and BPF fed groups received a concentrate mixture, CM1 with 25% rumen-protected protein (using barley, wheat bran, and mustard oil cake), BPP and BPPF groups received a second concentrate mixture, CM2 with 40% rumen-protected protein (using barley, de-oiled rice bran, and cottonseed cake). Bypass fat fed groups (BPF and BPPF) additionally were supplemented with 15 g BPF (Ca salt of long-chain fatty acids) per kg milk yield in their respective concentrate mixtures. Dry matter intake, body weights, body condition score, and total milk yield were similar between groups (P?>?0.05). Fat-corrected milk (FCM) production was improved (14.5%, P?>?0.05) in groups fed BPP and BPPF, while significant (19.45%, P?<?0.05) improvement was observed in BPF-fed group. Overall mean values of milk fat, solid not fat, protein, lactose, and total solids were found to be high (P?<?0.05) in treatment groups as compared with control values. It may be concluded that supplementation with BPP or BPF either alone or in combination positively influences the quality of milk produced in Murrah buffaloes during early lactation and BPF additionally had improvement on the quantitative trait of milk as well.

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39.
Interferon‐τ (IFN‐τ) has been recognized as the primary embryonic signal responsible for maternal recognition of pregnancy. Uterine endometrium produces both prostaglandin F2α (PGF2α) and prostaglandin E2 (PGE2). PGF2α is responsible for the luteolysis; however, PGE2 favours establishment of pregnancy by its luteoprotective action. In this study, the dose‐response effect of recombinant bovine IFN‐τ (rbIFN‐τ) on prostaglandin (PG) production by buffalo endometrial stromal cells cultured in vitro was studied. Buffalo endometrial stromal cells were isolated by double enzymatic digestion, initially with trypsin III followed by a cocktail of trypsin III, collagenase type II and DNase I and subsequently cultured till confluence. Further, cells were treated with different doses of rbIFN‐τ (0.001, 0.01, 0.1, 1.0 and 10 μg/ml) and keeping a separate set of control. Culture supernatant was collected after 6, 12 and 24 h of treatment. PG levels in the culture supernatant were measured by enzyme immune assay (EIA) and total cellular protein estimated by Bradford method. Results indicated that buffalo endometrial stromal cells following rbIFN‐τ treatment enhanced the secretion of both PGE2 and PGF2α, and also its ratio in a strict dose‐dependent manner with a significant increase (p < 0.01) in PGE2 production at 1 μg/ml dose of rbIFN‐τ and maximal stimulation for both PG was observed at 10 μg/ml. Further, both PG production and its ratio were increased significantly (p < 0.01) in a time‐dependent fashion in all the groups at 6, 12 and 24 h post‐treatment with highest level achieved at 24 h as compared with control. Absolute levels of PGE2 remained higher than PGF2α indicating PGE2 as the major PG produced by endometrial stromal cells. The dose‐dependent response of rbIFN‐τ signifies the importance of optimum concentration of IFN‐τ for the embryonic development especially during the critical period to establish successful pregnancy.  相似文献   
40.
Assessment of diversity in cultivated and wild useful Crotalaria L. distributed in different phytogeographical regions of India was made. Sites of germplasm collection were depicted on maps to facilitate planning and execution of collection and conservation programmes. In the present communication, information on useful and potential species of Crotalaria in India has also been documented for widening their scope in plant genetic resources management.  相似文献   
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