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61.
The chickpea leaf miner, Liriomyza cicerina (Rondani) (Diptera: Agromyzidae), is an important pest of cultivated chickpea (Cicer arietinum L.). A 2-year field study was carried out to screen a total of 126 Cicer germplasm for resistance to the leaf miner during the 2012 and 2013 growing seasons. Resistance was evaluated using a visual scale of 1–9, where 1?=?highly resistant and 9?=?very highly susceptible under natural infestation conditions. The results showed that two C. arietinum accessions, ILC 3397 and Sierra, had a score of 9 on the scale, being very highly susceptible. Three germplasm, one mutant (3304) and two breeding lines (LMR 140 and LMR 160) of C. arietinum, were found to be highly resistant with the scores ranging from 1.5 to 2 for resistance to the leaf miner. The mutant, 3304, was detected for the first time in this study as a highly leaf miner-resistant mutant of the cultivated chickpeas while the other two breeding lines had been previously reported as highly resistant against the leaf miner. In addition, two mutants and 14 breeding lines of C. arietinum and two mutants and one germplasm of C. reticulatum were identified as resistant having the scores from 2.1 to 3 on the 1–9 scale. The results suggest that these resistant germplasm may add a new dimension to chickpea breeding programs because they possess valuable traits for resistance against the pest. The resistant chickpeas that can be grown without using pesticides are important as environmental protection and reliable food source for human health.  相似文献   
62.
The potential of grafted watermelon for resistance toFusarium oxysporum f.sp.niveum on some Curcurbitaceae,Lagenaria, Luffa, Benincasa and commercial rootstocks was evaluated. Effects of grafting on yield and quality of diseased plants were evaluated. All grafted plants and rootstocks were resistant to the three known races (0, 1, and 2) ofF. oxysporum f.sp.niveum except watermelon cv. ‘Crimson Tide’, which was susceptible to race 2. Fruit yield was positively (21–112%) affected byLagenaria rootstocks but negatively affected (200–267%) byCucurbita rootstocks when compared with the control. While only minor differences in fruit quality were determined in control and grafted plants onLagenaria rootstocks, the quality parameters for watermelon grafted ontoCucurbita rootstocks were lower than in the control. The reasons for low yield and quality might be due to an incompatibility betweenCucurbita rootstocks and watermelon. These results showed that rootstock influence on disease resistance as well as yield and quality of scion fruit is important in determining the potential use of grafting applications in watermelon. http://www.phytoparasitica.org posting Feb. 2, 2003.  相似文献   
63.
Application of organic waste on agricultural land as a soil conditioner and fertilizing material has lately gained much attention. This study was conducted to determine the effects of vermicompost applications (0·5%, 1%, 2% and 4% w/w) on physical characteristics of soils with different textures (sandy loam, loam and clay), under laboratory conditions. The results indicated that in the higher soil aggregate fraction (>12·7 mm) aggregate fraction was limited at the three soils. Vermicompost applications in all three soils significantly increased organic matter content. When compared with control, the increasing rates in organic matter content were 14·0%, 23·8%, 42·0% and 90·2% for 0·5%, 1%, 2% and 4% vermicompost application doses, respectively. Vermicompost applications increased the wet aggregate stability and decreased the dispersion ratio of all the experimental soils in all aggregate size fractions. Overall, wet aggregate stability increased from 26·9% to 52·2% with the application rate of 4%. Correlation coefficient between organic matter content and wet aggregate stability was found as 0·918**. The lowest mean bulk density and the highest mean total porosity occurred when the most vermicompost was added. In all the soils studied, the highest permeability coefficients were gained with the application dose of 2%. As a result of increase in wet aggregate stability and decrease in bulk density, air permeability increased, and penetration resistance decreased significantly. The results obtained in this study have clearly indicated that the vermicompost application is an effective way to improve soil physical characteristics. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
64.
Valente  João  Sari  Bilal  Kooistra  Lammert  Kramer  Henk  Mücher  Sander 《Precision Agriculture》2020,21(6):1366-1384
Precision Agriculture - Knowing before harvesting how many plants have emerged and how they are growing is key in optimizing labour and efficient use of resources. Unmanned aerial vehicles (UAV)...  相似文献   
65.
Autolysis of protein isolates from vascular bundle and inner tuber tissues of potato (Solanum tuberosum) enhanced the inhibition of the angiotensin converting enzyme I (ACE), a biochemical factor affecting blood pressure (hypertension). The physiological age of the tuber affected the strength of ACE inhibition, the rate of its increase during autolysis, and the tuber tissue where ACE inhibition was most pronounced. The highest inhibitory activities (50% reduction in ACE activity achieved following autolysis at a protein concentration of 0.36 mg mL (-1)) were measured in tubers after 5-6 months of storage prior to sprouting. The rate of ACE inhibition was positively correlated with protease activity in tuber tissues. Amendment of the autolysis reaction with protein substrates from which bioactive ACE-inhibitory peptides may be released, for example, a purified recombinant protein or a concentrate of total tuber proteins, also enhanced ACE inhibition. Many tuber proteins including aspartic protease inhibitors were degraded during autolysis. The data provide indications of differences in the enzymatic activities confined to different parts of the potato tuber at different physiological stages. Results suggest that native enzymes and substrate proteins of potato tubers can be utilized in search of dietary tools to manage elevated blood pressure.  相似文献   
66.
In the second half of the nineteenth century, intensive renovation of vineyards took place due to the losses caused by phylloxera and local varieties were mostly replaced by several worldwide cultivars. Shift in genotypic structure in favor of modern cultivars resulted in the decrease or even disappearance of regionally typical local varieties. A total of sixty five Turkish grape genotypes, including 5 references (four cultivars and one rootstock), were genotyped with 16 SSR and 15 SRAP markers. Sixteen SSR primers generated a total of 60 SSR amplicons in which 43 were polymorphic with 73.4% average polymorphism percentage. A total of 111 well-resolved clear DNA bands were obtained from 15 SRAP primers. Of these bands, 53 were highly polymorphic with an average of 47.74%. Cluster analysis based on pooled marker data generated a well resolved grouping pattern. The analyzed genotypes grouped basing on their geographical belongings. There were many cultivar pairs on the dendrogram most of which occurred between 0.75 and 0.90 levels. SSR and SRAP data revealed a wide genetic variability as well as certain synonyms among the historical grape varieties cultivated for decades in local vineyards lengthwise the mountainous regions of Konya, Karaman and Mersin provinces. All the genotypes have been maintained in a grapevine germplasm glasshouse. Preservation and use of these endangered genotypes will be helpful to avoid genetic erosion and diversity loss in this part of Turkey. Also, the molecular data generated in this study could be of great use in determining the optimal breeding strategies to allow continued progress in grapevine breeding.  相似文献   
67.
The only supernovae (SNe) to show gamma-ray bursts (GRBs) or early x-ray emission thus far are overenergetic, broad-lined type Ic SNe (hypernovae, HNe). Recently, SN 2008D has shown several unusual features: (i) weak x-ray flash (XRF), (ii) an early, narrow optical peak, (iii) disappearance of the broad lines typical of SN Ic HNe, and (iv) development of helium lines as in SNe Ib. Detailed analysis shows that SN 2008D was not a normal supernova: Its explosion energy (E approximately 6x10(51) erg) and ejected mass [ approximately 7 times the mass of the Sun (M(middle dot in circle))] are intermediate between normal SNe Ibc and HNe. We conclude that SN 2008D was originally a approximately 30 M(middle dot in circle) star. When it collapsed, a black hole formed and a weak, mildly relativistic jet was produced, which caused the XRF. SN 2008D is probably among the weakest explosions that produce relativistic jets. Inner engine activity appears to be present whenever massive stars collapse to black holes.  相似文献   
68.
OBJECTIVE: Paternal smoking is highly prevalent in Asia, and tobacco may account for a large proportion of household expenditures among poor families. We sought to characterise the relationship between paternal smoking, child malnutrition and food expenditures. DESIGN: Data on smoking, household expenditures and child malnutrition were examined in a stratified multistage cluster sample of households in the Indonesia nutrition surveillance system. Main outcome measures were child wasting (weight-for-height Z-score < - 2), underweight (weight-for-age Z-score < - 2) and stunting (height-for-age Z-score < - 2), and severe wasting, underweight and stunting (defined by respective Z-scores < - 3). SETTING: In total, 175,583 households from urban slum areas in Indonesia. SUBJECTS: Children 0-59 months of age. RESULTS: The prevalence of paternal smoking was 73.8%. After adjusting for child gender and age, maternal age and education, and weekly per capita household expenditures, paternal smoking was associated with child stunting (odds ratio (OR) = 1.11, 95% confidence interval (CI) 1.08-1.14, P < 0.0001), severe wasting (OR = 1.17, 95% CI 1.03-1.33, P = 0.018) and severe stunting (OR = 1.09, 95% CI 1.04-1.15, P < 0.001). In households where the father was a smoker, tobacco accounted for 22% of weekly per capita household expenditures, with less money spent on food compared with households in which the father was a non-smoker. CONCLUSIONS: Among poor families in urban slum areas of Indonesia, paternal smoking diverts household money from food to tobacco and exacerbates child malnutrition.  相似文献   
69.
70.
Eurasian Soil Science - Splash erosion, the first step in water erosion process, occurs because of raindrops collusion with soil aggregates and pushing soil particulates into the air. The objective...  相似文献   
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