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991.
Summary The irrigation water in use at the Punjab University New Campus is of good quality except the water of one tubewell which
is relatively poor (high-salinity and low-sodium water) and has 0.45 ppm boron.
Water with a boron content of upto 3.00 ppm did not affect the germination of the seeds of wheat (Triticum vulgare L. var. Mexi-Pak) and there was some stimulation of the growth of seedlings by an increase in the concentration of boron
beyond 0.45 ppm. However, these seedlings, when transplanted to the soils supplied with waters containing different amounts
of boron, showed a decrease in their growth at higher concentrations of boron with their ageing, and when these plants were
about 100 days old and almost mature, their growth decreased significantly with an increase in the concentration of boron
to 2.00 or 3.00 ppm in the water supplied to them.
The growth of the plants of Mexi-Pak wheat is inversely related to the boron content of their tissues when it is more than
0.60 ppm.
Mexi-Pak wheat is semi-tolerant to boron. re]19750605 相似文献
992.
锈褐原花蝽在不同温度下的发育与积温必需条件 总被引:1,自引:0,他引:1
阿月浑子树木虱Agonoscena pistaciae Burckhardt and Lauterer (半翅目: 木虱总科)是伊朗园林树木阿月浑子树上常见的最具破坏性的害虫,其捕食性天敌锈褐原花蝽Anthocoris minki pistaciae Wagner在伊朗阿月浑子树种植区为该害虫的生防因子。本研究在17.5~35℃的8个恒温以及相对湿度55%±5%,光照周期16L∶8D的控制条件下,在A. pistaciae若虫上饲养这种捕食性花蝽的同时,调查温度对其发育的影响。结果表明:这种捕食性花蝽在17.5~32℃下可成功发育;然而在35℃下,卵不能孵化,且只有10%的若虫进入成虫阶段。30℃下从卵至成虫羽化的发育历期最短。据测算估计,这种捕食性花蝽的卵、若虫发育以及整个发育(卵至成虫)的积温分别为77,200和263度·日;卵、若虫和整个发育的低温度阈值分别为8.53, 9.2 和9.47℃。这些结果为建立阿月浑子树木虱的综合防治计划提供了宝贵的信息。 相似文献
993.
994.
Jessulat M Alamgir M Salsali H Greenblatt J Xu J Golshani A 《Archives of biochemistry and biophysics》2008,469(2):157-164
One of the key pathways for DNA double-stranded break (DSB) repair is the non-homologous end-joining (NHEJ) pathway, which directly re-ligates two broken ends of DNA. Using a plasmid repair assay screen, we identified that the deletion strain for RTT109 had a reduced efficiency for NHEJ in yeast. This deletion strain also had a reduced efficiency to repair induced chromosomal DSBs in vivo. Tandem-affinity purification of Rtt109 recovered Vps75 as a physical interacting protein. Deletion of VPS75 was also shown to have an effect on the efficiency of NHEJ in both the plasmid repair and the chromosomal repair assays. In addition, deletion mutants for both RTT109 and VPS75 showed hypersensitivity to different DNA damaging agents. Our genetic interaction analysis supports a role for RTT109 in DNA damage repair. We propose that one function of the Rtt109-Vps75 interacting protein pair is to affect the efficiency of NHEJ in yeast. Vps75 but not Rtt109 also seem to have an effect on the efficiency of DSB repair using homologous recombination. 相似文献
995.
T ?sterg?rd J Ek Y Hamid B Saltin O B Pedersen T Hansen O Schmitz 《Hormones et métabolisme》2005,37(2):99-105
Aerobic endurance training improves insulin sensitivity, and is of great importance in the prevention and treatment of type 2 diabetes. The improvement in insulin sensitivity and cardiovascular function through exercise is highly variable among individuals, and is probably partly determined by genetic components. This study evaluated the peroxisome proliferation-activated receptor-gamma2 ( PPAR-gamma2) Pro12Ala polymorphism and the angiotensin converting enzyme ( ACE) I/D polymorphism with respect to any potential influence that these highly prevalent polymorphisms may impose on changes in insulin sensitivity and maximal aerobic capacity induced by exercise. Seventy-nine healthy first-degree relatives of type 2 diabetic patients were compared to a control group consisting of 54 subjects without any family history of type 2 diabetes. All subjects had a normal OGTT. The groups were comparable with respect to age (34 +/- 7 vs. 33 +/- 7 years), gender ((m/f) 43/36 vs. 30/24) and BMI (25.7 +/- 2.6 vs. 25.3 +/- 2.5 kg/m (2)); p (all) = NS. Furthermore, a subgroup of 29 offspring and 17 control subjects were engaged in a standardized training program lasting ten weeks. Insulin sensitivity (hyperinsulinemic euglycemic clamp technique) and VO (2)max (exhaustive exercise test) was assessed before and after the training period. We will demonstrate the allelic frequency of the Ala-allele of the Pro12Ala polymorphism to be lower in offspring to type 2 diabetic patients (13.3 %) compared to control subjects (21.3 %); p < 0.05. In offspring only, the Pro12Ala polymorphism of the PPAR-gamma2 gene appeared to enhance weight changes brought about by exercise (Deltaweight = - 0.3 +/- 1.4 kg vs. - 1.8 +/- 1.8 kg; p < 0.05; (Pro/Pro vs. Pro/Ala + Ala/Ala) - suggesting possible gene-environment or gene-gene interactions. The ACE I/D polymorphism was not of significant importance in determining the capability of responding to exercise in terms of improvement in insulin sensitivity or maximal aerobic capacity. 相似文献
996.
997.
Role of Zinc in Rhizobacteria-Mediated Suppression of Root-Infecting Fungi and Root-Knot Nematode 总被引:2,自引:0,他引:2
Understanding the environmental factors that influence the rhizosphere and inner root colonization of the disease‐suppressive strains of fluorescent pseudomonads is an essential step towards improving the level and reliability of their biocontrol activity. Soil amendment with Zn at 0.8 or 1.6 mg/kg of soil alone or in combination with Pseudomonas aeruginosa IE‐6S+significantly reduced nematode penetration in tomato roots. Zn applied alone did not reduce root infection caused by Macrophomina phaseolina or Fusarium solani but did reduce when used in combination with IE‐6S+. Soil amendment with Zn at 0.8 or 1.6 mg/kg of soil alone or in conjunction with IE‐6S+ markedly suppressed Rhizoctonia solani infection. Plant height, fresh weight of shoot and protein contents of the leaves substantially improved when used with Zn, however, plants growing in the soil treated with 1.6 mg/kg of Zn in the absence of IE‐6S+ not only reduced plant growth but also showed necrotic symptoms on the leaves. Zn application in the soil decreased populations of IE‐6S+ both in the rhizosphere and root. A positive correlation between bacterial rhizosphere and inner root colonization was also observed. With an increase in nematode densities in the soil, nematode penetration and subsequent galling due to Meloidogyne javanica increased. Regardless of the nematode densities, Zn applied alone or in combination with IE‐6S+ caused marked suppression of M. javanica. At all the population densities of M. javanica, Zn enhanced the efficacy of IE‐6S+ to reduce nematode invasion and subsequent gall development. IE‐6S+ caused significant suppression of soil‐borne root‐infecting fungi both in Zn‐sufficient and Zn‐deficient soil although this suppressive effect accentuated in Zn‐sufficient soils. In the absence of IE‐6S+ and/or Zn, increased nematode densities in the soil significantly reduced plant height, fresh weight of shoot and protein contents of the shoots. With an increase in nematode densities, populations of IE‐6S+ in the rhizosphere and root increased regardless of the Zn application. However, Zn‐deficient soils supported larger populations of IE‐6S+ compared with those of Zn‐sufficient soils. 相似文献
998.
Hamid Galehdari Ali Mohammad Foroughmand Maryam Naderi Soorki Gholamreza Mohammadian 《Indian journal of human genetics》2009,15(1):9-12
BACKGROUND:
The common GJB2 gene mutation (35delG) has been previously reported from Iranian patients that were affected with nonsyndromic autosomal recessive deafness. We, therefore, for the first time, investigated the prevalence and frequency of the GJB2 gene mutation in the Iranian deaf population with Arabian origins.MATERIALS AND METHODs:
We amplified and sequenced the entire coding sequence of the GJB2 gene from 61 deaf patients and 26 control subjects.RESULT:
None of the analyzed samples revealed deafness-associated mutation.CONCLUSION:
This finding differs from several reports from Iran as we have focused on the GJB2 gene that possesses various mutations as the cause of congenital recessive deafness. 相似文献999.