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151.
Guangjun Guo Jianchang Gao Xiaoxuan Wang Yanmei Guo J.C. Snyder Yongchen Du 《Breeding Science》2013,63(3):239-245
An accurate and simple evaluation method is crucial for identifying whitefly resistance in tomato breeding. We developed an in vitro method for evaluating resistance of tomato leaves and tested this on wild and cultivated tomato varieties. We found that young leaves observed for whitefly oviposition after 8 hours provided appropriate comparative conditions. This method effectively distinguished resistance among tomato cultivars and wild species and also demonstrated significant difference in oviposition rates among leaf positions on susceptible cultivars. The in vitro test was as precise as in vivo test using intact plants and had advantages over in vivo test, and can be used for evaluating resistance in large populations. 相似文献
152.
153.
J.M. Scervino I. Sampedro M.A. Ponce M.A. Rodriguez J.A. Ocampo A. Godeas 《Soil biology & biochemistry》2008,40(9):2474
Exudates of Rhodotorula mucilaginosa, a yeast commonly found in the rhizosphere, increased hyphal length of the arbuscular mycorrhizal (AM) fungi Gigaspora rosea and Gigaspora margarita. Rhodotorulic acid (RA), a siderophore compound obtained from R. mucilaginosa exudates, increased hyphal length and branching. Thus, the increase in the number of entry points and the higher AM root colonization of tomato plants in the presence of RA can at least partially be explained by the positive effect of RA on the pre-symbiotic stages of the AM fungi. 相似文献
154.
Mkabwa L. K. Manoko Ronald G. van den Berg Richard M. C. Feron Gerard M. van der Weerden Celestina Mariani 《Genetic Resources and Crop Evolution》2008,55(3):409-418
Two hexaploid species of Solanum sect. Solanum are present in Africa: Solanum scabrum and S. nigrum. Solanum scabrum is a widely cultivated species and is used as a leafy vegetable, as a source of medicine and as a source of ink dye. In previous
studies a wide range of morphological diversity has been reported in this species and in some studies subspecies have been
proposed. Subspecies are also recognized in S. nigrum. However, it has not been established whether or not the morphological differences are reflected at the genomic level. The
present study applies AFLPs to study the genetic diversity in S. scabrum and its relationship to geographical provenance, morphological differences and the possible existence of subspecies within
S. scabrum and S. nigrum. The data obtained were analyzed with cluster analysis (using UPGMA and NJ). The results indicate that the genetic variation
within S. scabrum was higher within accessions than between accessions. Accessions did not cluster according to their geographical provenance,
indicating that accessions from different geographical areas were not significantly different genetically. The clustering
reflected neither morphological differences nor domestication status (cultivated or wild). The morphological differences exhibited
by S. scabrum could be due to selection by farmers for different plant types. The AFLP derived clustering pattern did not segregate the
subspecies recognized in S. scabrum and S. nigrum into separate subclusters. 相似文献
155.
番茄S-腺苷蛋氨酸脱羧酶基因SlSAMDC1的克隆与序列分析 总被引:1,自引:0,他引:1
以蔓陀罗S-腺苷蛋氨酸脱羧酶全长cDNA序列为信息探针, 筛选NCBI番茄EST数据库, 依据同源EST信息,经人工拼接、RT-PCR及RACE技术验证,获得了1个新的SAMDC基因家族成员,命名为SlSAMDC1(GenBank登录号:EF550528),并利用染色体步移技术克隆了879 bp的上游调控区域。SlSAMDC1 cDNA序列全长1 847 bp, 5′-UTR和3′-UTR分别长523 bp、241 bp;存在3个ORF(微型uORF、小型uORF和主ORF),主ORF编码360个氨基酸的SAMDC酶原;SlSAMDC1基因组序列全长3 648 bp,有3个内含子,均位于5′-UTR,所有内含子的剪切位点均符合真核生物“GT-AG”规则。SlSAMDC1基因与其它植物来源SAMDC基因同源性较高,与人、大肠杆菌以及酵母的同源性较低。表达谱分析发现,SlSAMDC1基因在番茄根、茎、叶、花蕾、果实等器官中均表达,果实中的表达量相对较高。生物信息学分析表明,SlSMDC1基因的上游调控序列存在多个顺式作用元件,如W-box、TATA-box、CAAT-box等。 相似文献
156.
157.
158.
RFLP analysis of a PCR amplified region of chloroplast DNA in eggplant and related Solanum species 总被引:1,自引:0,他引:1
RFLP analysis of a PCR amplified 3.2-kbp region of cpDNA bounded by the conserved sequences in rbc L and ORF 106 was performed
in eggplant (Solanum melongena), its related Solanum species, S. incanum, S. virginianum (= S. surattense), S. torvum, S.
aethiopicum (= S. gilo), S. aethiopicum (= S. integrifolium), S. violaceum (= S. indicum), S. violaceum (= S. sanitwongsei)
and S. mammosum and the reciprocal hybrids between S. aethiopicum (= S. integrifolium) and S. melongena 'Uttara'. The target
region of cpDNA was amplified correctly by PCR. The amplified products were digested with each of 10 restriction enzymes (Alu
I, Ase I, BamH I, Hinf I, Msp I, Rsa I, ScrF I, Sty I, Taq I and Xba I). Variations of restriction patterns among the species
were recognized after digesting the amplified products with each of the seven restriction enzymes, Taq I, Alu I, Rsa I, Sty
I, Ase I, Hinf I and Xba I. The restriction patterns divided the examined nine species into the following five clusters, 1)
S. melongena and S. incanum, 2) S. virginianum (= S. surattense), 3) S. torvum, 4) S. aethiopicum (= S. gilo), S. aethiopicum
(= S. integrifolium), S. violaceum (= S. indicum) and S. violaceum (= S. sanitwongsei) and 5) S. mammosum. The restriction
pattern with Alu I in each of the reciprocal hybrids between S. melongena 'Uttara' and S. aethiopicum (= S. integrifolium)
was identical with that of seed parent. The present study demonstrated the availability of the PCR-RFLP analysis of cpDNA
for assessing taxonomic relationships and identifying cytoplasmic parentage of interspecific hybrids in eggplant and related
Solanum species.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
159.
Summary Virulence of 12Fusarium oxysporum isolates was determined on three potato cultivars Late Harvest, BP1 and Kimberley Choice. The production of fusaric acid
by the 12F. oxysporum isolates was also determined. The aim of the study was to determine whether a correlation exists between fusaric acid production
and virulence ofF. oxysporum isolates. Late Harvest was the most tolerant and BP1 the most susceptible cultivar. Virulence ranking, order of theF. oxysporum isolates with the different cultivars corresponded with the mean of value of the ranking order for all three cultivars. A
correlation was found between virulence of isolates and fusaric acid production except for Late Harvest. Fusaric acid production
may play a major role in the development of dry rot in potato tubers. 相似文献
160.
Summary Potato crops in subtropical climates are often subjected to water stress, resulting in low yields and poor tuber quality.
The yield response of potato genotypes to water supply was investigated in six trials, three each in spring and autumn plantings.
Trials were conducted under automated rain shelters, using an irrigation boom to impose five soil water regimes.
The negative effect of water stress on tuber yield was more detrimental in spring than in autumn, because of higher atmospheric
evaporative demand and higher temperatures in spring. An average yield reduction of 68% was recorded for the most severely
stressed regime in spring plantings, while the mean reduction for the same treatment in autumn was only 42%. Genotypic differences
in yield response to drought were clearly illustrated in spring, but not in autumn. This suggests that the choice of genotypes
is only influenced by the availability of water in spring, when more drought tolerant genotypes should be used. 相似文献