跳至主要内容

In Vitro and Greenhouse Evaluation for Resistance to Early Blight of Potato Isolated from Alternaria alternata

Early blight of potato is caused by the fungus Alternaria alternata, one of the most destructive foliar diseases, especially in hot climates under irrigation. It usually causes leaf spots and tuber blight on potatoes. Potato resistance to early blight is a quantitative trait, and obtaining successful resistant cultivars is not simple. Some studies have shown that resistance to early blight is age-related: early-maturing cultivars are more susceptible than late-maturing cultivars.

In this study, the virus free potato seedlings were obtained from the National Plant Gene Bank of Iran during 2008-2009 and were inoculated in vitro with a culture filtrate of A. alternate. Seven cultivars (Ells, Picasso, Maradona, Marfona, Delta, Casmos and Desiree) were conducted that were propagated through nodal cutting every three month and kept in growth chamber at 25˚C ± 1˚C light with a period of 16 h light and 8 h dark. The leaflets received a 1000-μl droplet of the A. alternata culture filtrate and were inoculated by spraying with a suspension of 105 conidia/ml of isolate A. alternata in the greenhouse method. And disease severity assessments were taken every 2 days beginning at 3 day until 21 day. The experimental design was a completely randomized design (CRD) with three replications and seven genotypes, which had been infected with the two leaves of each iteration. In vitro selection of fungal isolates of A. alternata, chlorotic and necrotic symptoms began 1 to 2 days after inoculation, but the assessment of greenhouse symptoms appeared 6-10 days after inoculation. The area under the disease progress curve values were presented by analysis of variance (ANOVA), and they were compared using Duncan’s test (a = 0.01%).

In both methods, there was a significant difference between the potato genotypes (P < 0.01). For In vitro selection and evaluation greenhouse, the results showed that Casmos was the most sensitive cultivar and Marfona was the most tolerance cultivar.

Article by Hamid Reza Mirkarimi, et al, from Iran.

Full access: http://mrw.so/2eWtzH

Image by Jenn Brazil, from Flickr-cc.

评论

此博客中的热门博文

Does Immigration Promote the Investment of the Monopolistic Firm?

In the present paper, we examine the effect of increasing uncertainty of immigrants’ growth on the optimal timing of investment of a firm that has a monopolistic power over the labor market. It is revealed that when the uncertainty of immigrants’ growth is more than a threshold level, increasing uncertainty of immigrants’ growth accelerates the optimal timing of firms’ investment and enhances the economic growth, even if the uncertainty of immigrants’ growth is formulated by the geometric Brownian motion, which is in sharp contrast to the standard result that an increase in the uncertainty postpones the optimal timing. With an increase in the immigrants over the past ten years, workforces in the host countries have been growing significantly to the extent that the immigrants represent 70% of the increase in the workforce in Europe, and 47% in the United States as OECD indicates. In the present paper, we attempted to investigate the effect of increased uncertainty caused by the growi...

Education Policy Implementation: A Mechanism for Enhancing Primary Education Development in Zanzibar

Education is one of the fundamental rights of individuals; therefore, the government of a country needs to develop and strengthen educational policy and quality as well as to ensure that everyone has equal access to basic education. The improvement of access and quality of education in the world is becoming as an essential factor in development, whereas the basic education (primary school), is acknowledged as a foundation of the higher educational development for every country. To fulfill this goal, governments introduce several policies and procedures; however, it requires some reforms and participation from the politician, policymakers, and other stakeholders to re-examine educational policy so that it can lead to multiplication and betterment of the reforms. Educational reforms actually focus on accountability. A positive educational development and reform is very challenging and needs more effort and strategy on how to use and utilize the resources effectively as such it can achie...

Electron Spin and Proton Spin in the Hydrogen and Hydrogen-Like Atomic Systems

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52202#.VIj7tMnQrzE Author(s) Stanisław Olszewski * Affiliation(s) Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland . ABSTRACT The mechanical angular momentum and magnetic moment of the electron and proton spin have been calculated semiclassically with the aid of the uncertainty principle for energy and time. The spin effects of both kinds of the elementary particles can be expressed in terms of similar formulae. The quantization of the spin motion has been done on the basis of the old quantum theory. It gives a quantum number n = 1/2 as the index of the spin state acceptable for both the electron and proton ...