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101.
用10mmolL-1 硼酸处理Sensatinn芒果果实,日的在于了解硼酸时延缓成熟过程,尤其对延缓那些与成熟有关的生理变化是否有一定的作用。8d的成熟过程所观浏的结果表明.①硼酸处理的鲜果质量下降不如对照明显,果皮中叶绿素含量的变化也类似,②硼酸处理的果实中,果胶甲脂酶及多聚半乳糖醛酸酶的活性高于时照,且果胶甲酷酶的活性比多聚半乳糖醛酸酶的活性早2d达到峰值,⑧与对照相比较,硼酸能降低果实的呼吸作用,而时果肉的总糖含量没有影响。 相似文献
102.
Chris Ojiewo Emmanuel Monyo Haile Desmae Ousmane Boukar Clare Mukankusi‐Mugisha Mahendar Thudi Manish K. Pandey Rachit K. Saxena Pooran M. Gaur Sushil K. Chaturvedi Asnake Fikre NPVR Ganga Rao CV SameerKumar Patrick Okori Pasupuleti Janila Jean Claude Rubyogo Chigeza Godfree Essegbemon Akpo Lucky Omoigui Stanley Nkalubo Berhanu Fenta Papias Binagwa Michael Kilango Magdalena Williams Omari Mponda David Okello Mekasha Chichaybelu Amos Miningou Joseph Bationo Dramane Sako Sory Diallo Candidus Echekwu Muhammad Lawan Umar Richard Oteng‐Frimpong Haruna Mohammed Rajeev K. Varshney 《Plant Breeding》2019,138(4):487-499
Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement. 相似文献
103.
Jocelyn R Holt Lina Bernaola Kadie E Britt Chirs McCullough Morgan Roth Jennie Wagner Max Ragozzino Leslie Aviles Zhilin Li Forest Huval Manoj Pandey Benjamin W Lee Megan Asche Abigail Hayes Abigail Cohen Adrian Marshall Hannah E Quellhorst Rachel V Wilkins Valerie Nguyen Jacqueline Maille Rachel K Skinner John J Ternest Sarah Anderson Scott W Gula Kayleigh Hauri Julius Eason Megan Mulcahy Scott Lee James Michael Villegas Patricia Shorter 《Journal of insect science (Online)》2020,20(5)
Every year, the Student Debates Subcommittee (SDS) of the Student Affairs Committee (SAC) for the annual Entomological Society of America (ESA) meeting organizes the Student Debates. This year, the SAC selected topics based on their synergistic effect or ability to ignite exponential positive change when addressed as a whole. For the 2019 Student Debates, the SAC SDS identified these topic areas for teams to debate and unbiased introduction speakers to address: 1) how to better communicate science to engage the public, particularly in the area of integrated pest management (IPM), 2) the influential impacts of climate change on agriculturally and medically relevant insect pests, and 3) sustainable agriculture techniques that promote the use of IPM to promote food security. Three unbiased introduction speakers gave a foundation for our audience to understand each debate topic, while each of six debate teams provided a strong case to support their stance or perspective on a topic. Debate teams submitted for a competitive spot for the annual ESA Student Debates and trained for the better part of a year to showcase their talents in presenting logical arguments for a particular topic. Both the debate teams and unbiased introduction speakers provided their insight toward a better understanding of the complexities of each topic and established a foundation to delve further into the topics of science advocacy and communication, climate change, and the many facets of integrated pest management. 相似文献
104.
ABSTRACT: An experiment was conducted to investigate the effect of various organic acid (OA) supplementation on phosphorus (P) and nitrogen (N) retention by rainbow trout fed low fishmeal-based diets. Six experimental diets were formulated, and diet 0.5P was arranged as a positive control diet with 0.5% calcium phosphate and 0P as a negative control without additional P. Diets CA and LA were supplemented with 1% citric (CA), and lactic (LA) acids, respectively, and diets MHA and LTE were supplemented with 1% methionine hydroxy analog (MHA) and 1% liquid trace elements (LTE), respectively. Fish fed CA and LTE showed similar growth to that of the positive control diet. P retention was lowest in the 0.5P group and was elevated with CA and LTE diets. Therefore, in this study it is suggested that it might not be necessary to supplement the low fishmeal-based diet of rainbow trout with P if certain organic acids such as CA are added. 相似文献
105.
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108.
V.S. Pandey 《Veterinary parasitology》1980,7(4):357-362
The anterior mesenteric artery and its main branches, collected regularly from donkeys throughout a year, were examined for Strongylus vulgaris larvae. The mean monthly percentage of arteries infected varied from 61.5 to 100, with an overall mean of 90.5. The mean monthly number of larvae varied from 3 in January to 104 in April, with the annual mean of 32.6. A clear seasonal pattern occured in the worm burden and the age structure of larvae. The number of larvae was least in December–January, but rose gradually thereafter to reach a peak in April–May. A steep decline in June–July was followed by a progressive diminution until January. During summer and early autumn, the proportion of fifth-stage larvae was high. These observations indicate that S. vulgaris is an annual species in Morocco, infection occurring in late autumn and winter, development being completed in spring and summer, and sexually mature adults occuring in the gut mainly in summer and autumn. 相似文献
109.
SV AA Henriksen R.J. Jørgensen P. Nansen KR Sejrsen J. Brolund Larsen S. Klausen 《Veterinary parasitology》1976,2(3):259-272
The investigation was designed to study the gastro-intestinal helminth infection established in yearling calves with reference to fluctuations in the larval contamination of the herbage during the grazing season. In a 2 × 3 factor experiment, comprising six groups, each of six calves, a comparison was made between infection levels, growth rates etc. in calves grazing the same paddock over an entire season and calves moved before the July rise in herbage contamination to paddocks not grazed earlier in the same season. A comparison was also made between animals receiving no anthelminthic treatment, animals treated 3 weeks after the start of the grazing season and again when moved, and animals treated every 3 weeks during the season.Before July there were no weight gain differences between the various groups of calves. During the rest of the season, the calves which were moved gained 647–869 g, while those that remained on the same paddock, and were exposed to a high level of larval contamination gained only 81–361 g per day. The effect of anthelmintic treatment was less pronounced, though significant. The weight gains were correlated to a high degree with the larval contamination levels of the respective paddocks (r = ? 0.79) as well as with the serum pepsinogen (r = ? 0.75) and albumin levels (r = 0.75) of the calves and to a minor degree also with faecal egg counts (r = ? 0.45). The observed weight gain differences could not be accounted for by differences in grass quantity or quality. 相似文献
110.
A continuous increase in dry matter content in leaves of guava (Psidium guajava L.) was observed when their age increased, and also from the base to the top of the shoot. While the N, P, K, Zn and Cu content decreased, the levels of Ca, Mg, Na and Mn increased when age of leaf increased. With regard to position of leaves on the shoot, the levels of N, Ca and Mg increased from base to top, while the reverse was true for P, K, Na, Zn and Mn. No definite pattern was observed for Cu. Stabilization of all constituents was observed in 5-months old leaves borne on position V from the base of shoot. Thus, while considering the nutrient status of a tree as a whole, leaves of this age and position should be sampled. However, in certain cases the range of period and position for leaf sampling varied with the different elements, e.g. for Ca, 1- to 2-months old leaves should be sampled, while for Mn, leaves should be taken from positions II–IV of the shoot. 相似文献