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1.
Attack of tea plant (Camellia sinensis (L.) O. Kuntze) leaves by the tea mosquito bugHelopeltis theivora (Hemiptera: Miridae) was positively correlated to temperature and rainfall, and partially to humidity, as determined in 12
varieties during the period 2000–2002. The insect attack was severe during the months of May–September, which had high temperature
and rainfall, and led to severe loss of biomass due to curling and drying up of the leaves. The biochemical response of these
12 varieties of tea to attack by the insect was determined with special reference to oxidative enzymes and flavonoid flavor
components. Insect attack led to an increase in the activities of the oxidative enzymes peroxidase, ascorbate peroxidase and
polyphenol oxidase. Activities of phenyl alanine ammonia lyase generally decreased as a result of insect attack, which was
significant in the United Planters Association of South India (UPASI) varieties. A significant decrease in polyphenols was
also obtained in UPASI varieties. HPLC analysis of catechins revealed a decrease in some of the catechins in the infected
leaves. Analysis of theaflavins from infusion of healthy andHelopeltis-infested tea leaves revealed no changes.
http://www.phytoparasitica.org posting Dec. 19, 2004. 相似文献
2.
Ergot, caused by Claviceps africana , has emerged as a serious threat to sorghum hybrid seed production worldwide. In the absence of gene-for-gene-based qualitative resistance in commercial cultivars, varieties with high pollen production that can escape ergot infection are preferred. Recent demonstration of differences in ergot susceptibility among male-sterile lines has indicated the presence of partial resistance. Using chitin-specific fluorescin-isothiocyanate-conjugated wheat germ agglutin and callose-specific aniline blue, this study investigated the process of sorghum ovary colonization by C. africana . Conidia germinated within 24 h after inoculation (a.i.); the pathogen was established in the ovary by 79 h a.i., and at least half of the ovary was converted into sphacelial tissue by 120 h a.i. Changes in fungal cell wall chitin content and strategic callose deposition in the host tissue were associated with penetration and invasion of the ovary. The rate of ovary colonization differed in three male-sterile lines that also differed in ergot susceptibility. This work demonstrates a possible histological basis for partial resistance in male-sterile sorghum lines that could lay the foundation for variety improvement through further breeding and selection. 相似文献
3.
Organic zinc and copper supplementation on antioxidant protective mechanism and their correlation with sperm functional characteristics in goats 下载免费PDF全文
M Narasimhaiah A Arunachalam S Sellappan VK Mayasula PR Guvvala SK Ghosh V Chandra J Ghosh H Kumar 《Reproduction in domestic animals》2018,53(3):644-654
Trace minerals feeding had significant effects on sperm production and fertility with better absorption and proper utilization within the body for optimum reproductive function. Several studies have shown that more influenced trace elements in the diets of animals are copper (Cu) and zinc (Zn). Bucks showing deficiency of this mineral might affect the quality of semen production which in turn would affect the fertility. This experiment was thus designed to test the effects of organic Cu and Zn supplementation on antioxidants enzyme activities and sperm functional attributes in fresh semen of bucks. Forty bucks (n = 40, Aged 5 months) were assigned to ten groups of four animals in each group, supplemented (for a period of 8 months) with different levels of organic Zn: 20 mg (T2), 40 mg (T3) and 60 mg (T4), organic Cu: 12.5 mg (T5), 25 mg (T6), 37.5 mg (T7) and combined organic Zn and Cu: 20 + 12.5 mg (T8), 40 + 25 mg (T9), 60 + 37.5 mg (T10), respectively, per kg dry matter and no additional mineral diet (control; T1). One hundred and sixty semen samples were collected through electro‐ejaculator and analysed for sperm quantity, quality, acrosome intactness and plasma membrane integrity and correlated with the catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase enzyme activities in seminal plasma. The results indicated organic Cu and zinc supplemented bucks produced more sperm cells, had higher sperm concentrations, maintained higher (p < .01) sperm livability, plasma membrane and acrosome integrities, more motility and velocity. The increased antioxidant enzyme activities, reduced oxidative stress and lowered lipid peroxidation were positively correlated (p < .05) with the sperm functional attributes. In conclusion, organic Cu and Zn supplement to male goats showed protective roles against oxidative damage and maintained better fresh semen characteristics. 相似文献
4.
5.
Keneisenuo Keneisenuo MVSc Om Prakash Choudhary PhD Pranab Chandra Kalita PhD Priyanka Choudhary PhD Arup Kalita PhD Probal Jyoti Doley MVSc Jitendra Kumar Chaudhary PhD 《Anatomia, histologia, embryologia》2021,50(3):500-511
The present study reports data on the skull bone morphometry of barking and sambar deer. The skulls of adult barking deer (n = 6) and sambar deer (n = 6) of either sex (n = 3 males and n = 3 females) were collected from the Aizawl Zoological Park, Aizawl, Mizoram, India, with official permission from the Government of Mizoram. Anatomically, barking and sambar deer's skulls were elongated, pyramid-like, dolichocephalic and consisted of thirty-two cranial and facial bones. The cranial bones were eleven (three single and four paired), comprising of occipital, sphenoid, ethmoid, frontal, interparietal, parietal and temporal. The facial bones were twenty-one (one single and ten were paired), consisting of the maxilla, premaxilla (incisive), palatine, pterygoid, nasal, lacrimal, zygomatic (malar), vomer, turbinates, mandible and hyoid. In the present study, altogether 41 different measurements were taken morphologically and 6 different indices were applied. The obtained morphometrical parameters were significantly (p < .01, p < .05) higher in males than females of both species. Species wise, all obtained parameters were higher in sambar deer than barking deer. The obtained 41 different skull parameters and 6 indices showed statistically significant differences (p < .01 and p < .05) between both sexes of barking and sambar deer; however, practically these differences were meagre. The present morphometrical study on the skull of both species can help the wildlife professionals and zoo veterinarians determine the sex of these animals and differentiate it from other domestic and wild small ruminants for solving veterolegal cases. This study's findings will also motivate and assist other comparative studies with various domestic and wild small ruminants. 相似文献
6.
Chandra M Singh BR Shankar H Agarwal M Agarwal RK Sharma G Babu N 《Preventive veterinary medicine》2007,80(1):1-8
We screened serum samples of 1024 goats slaughtered for chevon in Bareilly in Northern India for Salmonella antibodies with indirect ELISA, MAT-H (microagglutination test using flagellar antigens e, n, x and 1, 5) and MAT-O (microagglutination test using somatic antigens 4, 12 and 3, 10, 15). Salmonella antibodies were detected in 48, 8 and 40%, goats using Salmonella-cytotoxi-I ELISA, MAT 'H' and MAT 'O', respectively. After adjusting for test accuracy, the seroprevalence were highest for Salmonella-cytotoxi-I ELISA (46%) followed by agglutinins against 'O' 3, 10, 15 (15%) and negligible for other agglutinins. With all 5 tests, prevalence of Salmonella antibodies was significantly higher in females than in males. No significant difference was evident in prevalence of Salmonella antibodies to different antigens in different age groups of male goats except for e, n, x agglutinins that were significantly more prevalent in young adult (<6-18 months) males than in adult (>18 months of age) or young (< or =6 months of age) goats. On the other hand, in females, prevalence of Salmonella-cytotoxin-I antibodies and e, n, x agglutinins differed significantly among three age groups, being the most prevalent in adult goats. As expected, the results of different tests had little or no correlation because the different tests targeted antibodies to different antigens. 相似文献
7.
Thakur Shikha Verma Subhash Chander Sharma Prem Lal Chandel Rajeshwar Singh Sharma Priyanka Sharma Shubham Sharma Prajjwal 《Phytoparasitica》2023,51(2):189-198
Phytoparasitica - Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae) is one of the most promising, effective and a common endoparasitoid of different aphid species including cabbage aphid,... 相似文献
8.
Sandra R. Ethridge Saket Chandra Anna M. Locke Wesley J. Everman David L. Jordan Micheal D.K. Owen Ramon G. Leon 《Pest management science》2023,79(10):4048-4056
BACKGROUND
The potential of weed species to respond to selection forces affecting the evolution of weedy traits such as competitive ability is poorly understood. This research characterized evolutionary growth changes in a single Abutilon theophrasti Medik. population comparing multiple generations collected from 1988 to 2016. A competition study was performed to understand changes in competitive ability, and a herbicide dose–response study was carried out to assess changes in sensitivity to acetolactate synthase-inhibiting herbicides and glyphosate over time.RESULTS
When grown in monoculture, A. theophrasti biomass production per plant increased steadily across year-lines while leaf number decreased. In replacement experiments, A. theophrasti plants from newer year-lines were more competitive and produced more biomass and leaf area than the oldest year-line. No clear differences in sensitivity to imazamox were observed among year-lines. However, starting in 1995, this A. theophrasti population exhibited a progressive increase in growth in response to a sublethal dose of glyphosate (52 g a.e. ha−1), with the 2009 and 2016 year-lines having more than 50% higher biomass than the nontreated control.CONCLUSION
This study demonstrates that weeds can rapidly evolve increased competitive ability. Furthermore, the results indicate the possibility of changes in glyphosate hormesis over time. These results highlight the importance of the role that rapid (i.e., subdecadal) evolution of growth traits might have on the sustainability of weed management strategies. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献9.
The problem of real-time irrigation scheduling under limited water supply is considered. The goal is to develop an irrigation operation policy which maximizes crop yields and is responsive to current season changes in weather and other variables. Because irrigation decisions are sequential and dependent on crop and soil water status, and also because crop yields can only be known at the end of the season, the decisions are arrived at by a two-stage process. In the first or the design stage, irrigations are planned for the entire season at weekly intervals using historical data and an optimal irrigation scheduling model. In the second stage, the decisions for the subsequent weeks are revised each week after updating the status of the system with real time data up to that week and solving the irrigation optimization model once again for the new conditions. Thus, each week an irrigation decision is made, the entire planning horizon is kept in view. The procedure is illustrated by application to a case study. 相似文献
10.