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1.
Corné M. J. Pieterse Pierre J. G. M. de Wit Francine P. M. Govers 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(Z2):85-92
The fungal pathogenPhytophthora infestans is the causal organism of late blight, one of the most devastating diseases of potato. In the past, various aspects of the potato-P. infestans interaction have been studied extensively. In this paper we briefly review the current knowledge of the molecular events associated with the interaction and in addition we discuss a new approach for analyzing the molecular basis of pathogenicity ofP. infestans. 相似文献
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Flavia O S van Cleef Jos C B Dubeux Jr. Harley D Naumann Erick R S Santos Lynn E Sollenberger Joo M B Vendramini Martin Ruiz-Moreno Francine M Ciriaco Nicolas DiLorenzo 《Journal of animal science》2021,99(8)
An experiment was conducted to evaluate the effects of different proportions of ‘Au Grazer’ sericea lespedeza [SL, Lespedeza cuneata (Dum. Cours.) G. Don], a legume rich in condensed tannins (CT), on nutrient intake and digestibility, and to estimate methane (CH4) emissions and 13C isotopic composition (δ13CCH4) from beef steers consuming a forage-based diet. Twenty-five Angus-crossbred steers were distributed in a randomized complete block design (344 ± 48 kg initial BW), and randomly assigned to one of five treatments: 0SL, 25SL, 50SL, 75SL, and 100SL, diets containing 0%, 25%, 50%, 75%, and 100% of SL hay, respectively, mixed with ‘Tifton-85’ bermudagrass hay (Cynodon spp.). The study was carried out for two experimental periods of 21-d each. The statistical model included the fixed effect of treatment and random effects of block, experimental period, and their interaction. Apparent total tract digestibility of crude protein, neutral detergent fiber, and acid detergent fiber was linearly decreased (P < 0.001) by the inclusion of SL. No effects were observed for total CH4 emissions per day, nor for CH4 relative to organic matter intake or digestible organic matter with the inclusion of SL. However, emission of CH4 in relation to intake of CT was affected by treatment (P < 0.001). A linear (P < 0.001) decrease and a quadratic effect (P < 0.001) were observed for δ13C of diets and gas, respectively, in which diets and enteric CH4 with greater inclusion of SL were more depleted in 13C. Moreover, the difference in δ13C between diets and gas (Δδ13C) had a linear decrease (P = 0.001) with the inclusion of SL. The model developed to predict the C3 proportions in the enteric CH4 fitted to predicted values (P < 0.0001). Therefore, greater proportions of SL resulted in lesser CH4 emission when CT intake was considered and the isotopic composition from enteric CH4 was able to predict the contribution of SL in the emissions. 相似文献
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New Forests - Permanent landscape attributes such as topography (elevation [m]) and microtopography (local variation in elevation [cm]) can increase the risk of cold air drainage down-slopes and in... 相似文献
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Most potato transgenic research has focused on development of resistance to pathogens and modification of potato physiology.
Many transgenes, particularly those conferring pathogen resistance, could substantially lower potato production costs in developing
countries. However, transgenes have not been reported in sexually propagated 4x-2x potato hybrids commonly grown in developing countries. Two transgenes,the Bacillus thuringiensis cry3Aa endotoxin protein gene and the PVY°coat protein gene, were engineered intodiploid and tetraploid potato using Agrobacterium tumefaciens-mediated transformation. Cry3Aa was produced at high levels in several lines while the PVY° coat protein was not expressed.
Diplandroid and tetraploid genotypes were crossed to produce transgenic 4x-2x hybrids. Genetic transformation had no discernable effect on fertility ofthe primary transformants, germination of4x-2x seed derived from the transformants and agronomic performance(tuber set, average tuber weight and total tuber yield) of the
4x-2xhybrids. The transgenic 4x-2xhybrids produced non-viable pollen and could only be crossed as female parents. Results suggest that transgenes, such ascry3Aa, could be expressed in 4x-2x hybrids to lower costs of production with no significant effect on plant phenotype.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Summary True protein content among tubers within a plant of Solanum tuberosum cv. Oneida was found to be negatively correlated with tuber size. A similar study of S. phureja genotype 148-17 revealed no correlation. Tuber protein was determined for 250 genotypes in each of four hybrid potato populations in a factorial mating design with four potato cultivars as stylar parents mated to four groups of pollen parents (4x cultivars, 4x high protein selections, 2x S. phureja, 2x high protein S. phureja). The hybrid population derived from the 4x high protein selections was significantly higher in protein content than the other populations. High estimates of general combining ability for tuber protein content were found for both stylar and pollen parents. Poor photoperiodic adaptation to growing conditions in northern latitudes was a possible explanation for the variable protein phenotypes typical of S. phureja and the lack of transmission of the high protein character in phureja to 4x-2x hybrids. Although protein content was negatively correlated with total yield, high protein segregates with good yield potential were identified in all four populations.Scientific Journal Series Article 11, 616 of the Minnesota Agricultural Experiment Station. 相似文献
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Complex potato hybrids were derived through unilateral sexual polyploidization between Solanum tuberosum cv. Atlantic and
11 diploid hybrids that produced 2n pollen through co-orientation of second division spindles. The hybrids represented the
following genomic compositions: TAPB, TAPC, and TAPM where T = S. tuberosum, A = S. andigena, P = S. phureja, B = S. berthaultii,
C = S. chacoense, and M = S. microdontum. The B, C, and M components of the hybrids had been selected from heat tolerant accessions.
The heat tolerance and agronomic performance of the hybrids were assessed under both controlled environments and field tests.
The hybrids exhibited good tuberization potential (tuber number, tuber weight and percent plants producing tubers) under heat
stress conditions in controlled environments. Under severe heat stress conditions in the field in Israel, many of the hybrids
tuberized when Atlantic failed to produce any tubers at all. Under more moderate heat stress in Virginia, the complex hybrids
exhibited total tuber yield not significantly different from Atlantic, although the tuber set per plant was greater. However,
the complex hybrids were more tolerant to heat necrosis and hollow heart than Atlantic. Total glycoalkaloids in field-grown
tubers did not exceed the acceptable limit for 13 of 26 selections examined.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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与马铃薯晚疫病菌无毒基因Avr1连锁的AFLP标记 总被引:11,自引:1,他引:11
以具有和不具有无毒基因Avr1表现型的马铃薯晚疫病菌株80029 (AVR1) 和88133 (avr1)以及其杂交F1代50个菌株群体为试材,限制性内切酶PstI和HhaI为酶切组合,采用荧光AFLP技术和混合分组分析法(BSA),通过256对引物筛选得到了5个与Avr1连锁的候选AFLP标记并进行了菌株个体验证,遗传分析表明5个标记中有2个标记与Avr1连锁且在F1代中共分离,无交换重组发生。 相似文献
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