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1.
The impact of soil (1, 2 kg ha?1) and foliar (100, 200 mg L?1) boron (B) with control (no B) was evaluated on phenology and yield formation of Camelina each applied at stem elongation and flowering stages. Foliar (200 mg L?1) or soil B (2 kg ha?1) resulted in earlier flowering and maturity, increased fruit bearing branches (19.68%), number of siliqua, seeds per siliqua (4.6%), biological yield (15%), seed yield (24%), harvest index (11.4%) and oil contents (23%) than no B. Increased fruit bearing branches, seed filled siliqua or seed numbers, harvest index and oil quality can be attributed to changes in dry matter accumulated of stem with simultaneous increase in siliqua dry weight with foliar or soil applied B. In crux, foliar (200 mg L?1) or soil applied (2 kg ha?1) B seems promising to improve seed and oil yield, harvest index of Camelina sativa under B deficient condition.  相似文献   
2.
BACKGROUND: Rhizobacteria have a good potential to suppress soilborne diseases, but their efficacy against sugarcane pests is rarely reported. Bacterial strains isolated from the rhizosphere of sugarcane were evaluated for their potential to suppress red rot disease on two susceptible varieties, Co‐1148 and SPF‐234, under field conditions. The strains were also characterised for the production of secondary metabolites associated with their antagonistic activity. RESULTS: One out of four strains, the Pseudomonas putida strain NH‐50 (EU627168), reduced disease severity by 44–60% in different field trials. This potent antagonistic strain produced pyoluteorin antibiotic, as confirmed by high‐performance liquid chromatography (HPLC). The PltB gene involved in pyoluteorin synthesis was amplified from the P. putida strain NH‐50 and sequenced. The extracellular metabolites and volatile and diffusible antibiotics secreted by the tested strains inhibited mycelial growth of Glomerella tucumensis (Speg.) Arx & E Mull in vitro by 7–55%. CONCLUSION: The pyoluteorin‐producing bacteria P. putida strain NH‐50 significantly reduced disease severity on both sugarcane varieties, irrespective of fungal inoculation, i.e. either inoculated through stem or through soil. This strain also possesses other plant growth characteristics and can be used as a biopesticide for sugarcane crop. Copyright © 2011 Society of Chemical Industry  相似文献   
3.
Summary The competitive ability of inoculated and indigenous Rhizobium/Bradyrhizobium spp. to nodulate and fix N2 in grain legumes (Glycine max, Vigna unguiculata, Phaseolus vulgaris) and fodder legumes (Vicia sativa, Medicago sativa, and Trifolium subterraneum) was studied in pots with two local soils collected from two different fields on the basis of cropping history. The native population was estimated by a most-probable-number plant infectivity test in growth pouches and culture tubes. The indigenous rhizobial/bradyrhizobial population ranged from 3 to 2×104 and 0 to 4.4×103 cells g-1 in the two soils (the first with, the second without a history of legume cropping). Inoculated G. max, P. vulgaris, and T. subterraneum plants had significantly more nodules with a greater nodule mass than uninoculated plants, but N2 fixation was increased only in G. max and P. vulgaris. A significant response to inoculation was observed in the grain legume P. vulgaris in the soil not previously used to grow legumes, even in the presence of higher indigenous population (>103 cells g-1 soil of Rhizobium leguminosarum bv phaseoli). No difference in yield was observed with the fodder legumes in response to inoculation, even with the indigenous Rhizobium sp. as low as <14 cells g-1 soil and although the number and weight of nodules were significantly increased by the inoculation in T. subterraneum. Overall recovery of the inoculated strains was 38–100%, as determined by a fluorescent antibody technique. In general, the inoculation increased N2 fixation only in 3 out of 12 legume species-soil combinations in the presence of an indigenous population of rhizobial/bradyrhizobial strains.  相似文献   
4.
Bread-making quality of wheat flour is largely determined by the accumulation, concentration and composition of the proteins in the grain, which are influenced by genetic (G) and environment (E) variation and their interactions. We have therefore evaluated the importance of G and E factors and their interactions in determining the accumulation and composition of the proteins in the wheat grain. The cultivar determined development time (CDDT), together with the amount and timing of N application, played a significant role in determining the accumulation and final composition of the wheat grain proteins, explaining 21–59% of the variation. At low temperature, N application both at spike formation and at anthesis explained the highest proportion of variation (36%) in the percentage of sodium dodecyl sulphate (SDS) unextractable polymers in the total amount of polymers (% UPP), while at high temperature CDDT contributed most to the variation in % UPP (20%). The largest contributor to variation in the amount of total SDS extractable proteins (TOTE) was N application at anthesis, both at low and high temperatures (12% and 36%, respectively). Thus, the climate should be considered in recommendations for improving the protein quality and thereby the bread-making quality of wheat.  相似文献   
5.
Quinoa is recently introduced to Pakistan as a salt‐tolerant crop of high nutritional value. Open field trials were conducted to evaluate its performance on normal and salinity/sodicity‐degraded lands at two locations of different salinity/sodicity levels, S1 (UAF Farm, Normal Soil), S2 (Paroka Farm UAF, saline sodic), S3 (SSRI Farm, normal) and S4 (SSRI Farm, saline sodic) during 2013–2014. Two genotypes (Q‐2 and Q‐7) were grown in lines and were allowed to grow till maturity under RCBD split‐plot arrangement. Maximum seed yield (3,062 kg/ha) was achieved by Q‐7 at normal field (S1) soil which was statistically similar with yield of same genotype obtained from salt‐affected field S2 (2,870 kg/ha). Furthermore, low yield was seen from both genotypes from both S3 and S4 as compared to S1 and S2. Q‐7 was best under all four conditions. Minimum yield was recorded from Q‐2 (1,587 kg/ha) at S4. Q‐7 had higher SOD, proline, phenolic and K+ contents, and lower Na+ content in leaves as compared to Q‐2. High levels of antioxidants and K+/Na+ of Q‐7 helped to withstand salt stress and might be the cause of higher yields under both normal and salt‐affected soils. Seed quality (mineral and protein) did not decrease considerably under salt‐affected soils even improved seed K+, Mg2+ and Mn2+.  相似文献   
6.
An understanding of variation in fruit quality in relation to tree age can help understand the issue of poor fruit quality in young orchards; however, limited information is available on the citrus fruit. In this study, the endogenous nutritional status in rind, rag, and leaves; pectin status in rind and rag; and anatomical fruit growth parameter in rind tissues were studied in ‘Kinnow’ mandarins fruit during their development on trees from three age (6-, 18-, and 35-year-old) groups. In older (35-year-old) trees, rind, rag, and leaf nitrogen (N), phosphorus (P), and potassium (K) concentrations were superior. In fruit from all tree age groups, total pectin and protopectin reduced; however water-soluble pectin (WSP) improved. In rind tissues harvested from young (6-year-old) trees, cell density was more while cell size was less. In all tree age groups, cell density in rind tissues correlated negatively with rind WSP.  相似文献   
7.
1. The present study investigated the effects of encapsulated benzoic acid (BA) supplementation in broiler feed on performance and gastrointestinal microbiota.

2. Eighty broilers were randomly divided into two groups. Birds in the control group were fed on maize–soybean-based diets. Birds in the treatment group were provided the same diet supplemented with 2 g/kg BA encapsulated in a vegetable oil matrix.

3. At the end of the trial (d 35), pH, bacterial composition and metabolites were determined in the crop, jejunum, ileum and caecum.

4. Growth performance variables and pH were not significantly different.

5. BA concentration decreased rapidly in the proximal gut. However, the treatment diet showed higher BA in the crop, jejunum, ileum and caecum.

6. Total lactate in the crop and D-lactate in the jejunum was higher in the BA treated group. Caecal total and branched chain fatty acids were decreased due to the treatment.

7. Lactobacilli populations were significantly altered by BA supplementation. A trend for increased lactobacilli was observed in the crop, while it became significant in the jejunum and ileum. Lactobacillus species responded differently to the treatment. Four of 5 measured Lactobacillus species, particularly in the ileum, followed the course observed for total lactobacilli; only Lactobacillus salivarius was not modified.

8. Correlation analysis showed that BA modified the intestinal microbiota. Lactobacilli correlated negatively to all studied clostridial clusters and enterobacteria. Clostridial clusters IV and XIVa were significantly increased in the jejunum, whereas only clostridial cluster XIVa was increased in the caecum.

9. Encapsulated BA modified the intestinal microbiota which can lead to the conclusion, that the main beneficial mode of action of BA in the gut appears to be the enhancement of lactic acid bacteria, which in turn may act as a vanguard against pathogens.  相似文献   

8.
One sixth of the world’s population is suffering from hidden hunger that indicates a gross malnutrition particularly among children and women of third world countries. The deficiency of micro nutrients, especially iron (Fe) causes a number of ailments such as megaloblastic anemia and neural tube defects in poor population. There is a dire need to supplement iron in the diet. Current efforts implicate fortification of wheat flour and other grains with different iron formulations such as ethylenediaminetetraacetic acid (EDTA), FeSO4 and elemental iron. However, all such interventions are not sustainable due to logistic and quality assurance problems in resource-limited settings. For a long term solution, development of crop plants with increased micronutrients and iron bioavailability is essential. Therefore, biofortification of cereal grains using translational genomics approaches for enhancement of folate through genome editing in cereals is inevitable to mitigate the folate deficiency in poor remote population in a cost effective manner.  相似文献   
9.
Zinc (Zn) is an important micronutrient for rice (Oryza sativa L.) production and its deficiency has been observed in various production systems. High grain Zn concentration is equally important for high rice yield and human health. In this work, the effects of Zn fertilization on seedling growth, grain yield, grain Zn concentration, and their association with root traits were studied under alternate wetting and drying (AWD), aerobic rice (AR), system of rice intensification (SRI), and continuous flooding (CF). Zinc fertilization (15 kg ha?1) improved nursery seedlings chlorophyll and Zn concentrations, root length, and number of roots with highest values observed in CF. At harvesting, maximum plant height, panicle length, total and panicle bearing tillers, and kernel yield were found with Zn addition in AWD and CF rice systems. Mid season drainage provided at maximum tillering and Zn fertilization increased its concentration in leaves, culms, panicles, and grains under CF and AR at physiological maturity. Most of Zn applied was allocated into culms and panicles, nevertheless, a significant increase in grain Zn concentration was also observed in all production systems. Association of leaf Zn with grain Zn concentration was stronger than with culm and panicle Zn. The results indicate that Zn application after rice nursery transplanting is more important for grain Zn enrichment in all rice systems than for increase in grain yield in all systems except AWD where grain yield was also increased. More grain yield in CF and AWD as compared to SRI and AR can also be attributed to decreased spikelet sterility and to better Zn phyto‐availability in these rice systems at physiological maturity.  相似文献   
10.
ABSTRACT

The knowledge about heterosis breeding of achene yield in sunflower is known; however, dissection of the genetic components of achene yield and seed quality traits is limited. Therefore, the prescribe study was conducted using Line × Tester design to determine combining abilities, and about the maternal-and-paternal gene actions involved in achene yield and seed quality traits in 21 single cross hybrids. Significant mean differences for achene yield and seed quality traits were observed, with total attributed variation (R2?=?0.89). Principal component analysis (P?<?0.05) explained 92.6% variation and using factor analysis, we found factor 1 had primary variables (AW, AL, AT, HD, PH, PC, LA and OC) contributed 35.6% variation to achene yield. Combining ability analysis showed the positive general combining ability for E%, HD, PH, 100 AW and AYP in parental inbred lines, whilst, hybrids had positive specific combining ability for E%, HD, PH, 100 AW, DTF, DTM, OA, LA, OC and AYP. Females contributed significantly higher (P?<?0.05) for AYP, E%, HD, NWPH, PH, 100 AW, LA and OA than that of males. Two-way hierarchical clustering showed the most promising hybrid H5 (A-18?×?G-79) in Cluster V. The hybrid H5 also showed heterosis, heterobeltosis and commercial heterosis, therefore, genetic exploitation of H5 is highly desirable in future breeding to map QTLs/genes in arid/semi-arid zones and /or similar growing conditions to boost up yield and seed quality traits.  相似文献   
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