Dry mycelium (DM) of Penicillium chrysogenum (PEN), a waste product of the pharmaceutical industry, is used as an organic fertilizer for agricultural production. Our previous studies have indicated that DM of PEN is effective in controlling a number of soil born fungal diseases, but the mode of action is unclear. In the present study, DM of PEN was extracted with water and applied to the roots of the Bt (Bacillus thuringiensis) transgenic cotton (Gossypium hirsutum) cultivar SCRC 21. The efficacy in controlling Fusarium oxysporum f.sp vasinfectum (Fov) and Verticillium dahliae Kleb (Vd), as well as the accumulation of pathogenesis-related (PR) protein transcripts in the plants were examined. The results showed that soil drench with PEN provided significant protection against Fov and Vd. The controlling efficacy of PEN was dose-dependent, and the highest efficacy was obtained with 5-7% PEN. Soil drench with 5% induced the accumulation of six PR protein transcripts, PR-1a, PR-1b, PR-2, PR-3, A-C and B-C in cotyledons of cotton seedlings, suggesting that these PR proteins may be involved in induced resistance against wilt diseases in cotton by PEN. It seems that DM of PEN represents a new agent capable of inducing both resistance and the accumulation of PR protein transcripts.

Bronotak 12 DS, an already recommended bactericide, in mixture with the recommended rates of the fungicide Raxil (tebuconazole) and the insecticide Gaucho (imidacloprid) were evaluated for their efficacy to control pre- and post- emergence damping off, bacterial blight and flea beetles in commercial cotton cultivars. All tested rates and mixtures significantly reduced damping- off and bacterial blight diseases and flea beetle damage compared with the untreated control in both seasons and cultivars. They gave comparable control and seed cotton yield to the standard treatment. Seed cotton yield of Barakat 90 was increased by Bronotak mixtures by 13-36% and 50-82% in seasons 2004/05 and 2005/06, respectively compared to the untreated control. The increase in Barac (67) B was 18-35 and 21-42 % in seasons 2004/05 and 2005/06, respectively

In years 2001-03 the influence of resistance stimulators and N fertilization on the occurrence of spring barley diseases was investigated. The experiment was carried out at Zlotniki Experimental Station (Poland) on a sandy loam soil classified as Albic Luvisols Treatment included resistance stimulators (Bion 50 WG, ComCat, control -untreated), and four levels of nitrogen fertilization (0, 30, 60, 90 kg N/ha). The occurrenced diseases of spring barley was depended on weather conditions and one of them on nitrogen fertilization. Resistance stimulators decreased infection of spring barley by Pyrenophora teres, Rhynchosporium secalis, Blumeria graminis and Puccinia hordei. There was no difference between Bion 50 WG and ComCat effectiveness in diseases reduction. In laboratories and greenhouse experiments effectiveness of harpin (Messenger) application to seeds and plants of corn, cotton and soybean was investigated. Results of these experiments showed positive influence of the protein on germination and growth of the plants. Appearance of the stress seams to be an important agent for stimulator activeness estimation

Possible contributions of genetic innovations to improvement in the competitivity of the cotton production and marketingchains in Africa. The 3 components of the profi tability of the cotton production and marketing chains which can beimproved following the development of genetic innovations concern: (i) the production cost of the cottonseed, thanks tothe introduction in the cultivated varieties of genes allowing to decrease the impact of the biotic (weeds, pests and diseases)and abiotic (drought, soil poverty, acidity and salinity) constraints, (ii) the cost of the ginning of the cottonseed and (iii) thequality of the various products of the cotton plant (fi ber, cakes, oil). The priorities to be retained for Africa regarding these3 components must absolutely take into account the characteristics of the local farming systems. In Africa, most of cottonis produced in farms of relatively small size with a low level of mechanization of the farming operations and a recourseto quantities of manure and pesticides defi nitely lower than elsewhere in the world whereas the levels of biotic and abioticconstraints are at least as high there as in the other continents. In this context, the priority of the genetic improvement programsshould aim at developing varieties with high quality fi ber, multi-resistant to the biotic and abiotic adversities, with the highestpossible ginning outturn and presenting an inhibition of the synthesis of the gossypol only at seed level. According to the localpriorities and resources available, the development of the new varieties should ideally be done by combining the approachesof the traditional genetic improvement assisted by the use of DNA markers and the functional genomics tools to direct theimplementation of targeted genetic transformations. This will not be possible without the maintenance of strong structures ofgenetic improvement directly in contact with the fi eld realities specifi c to each great zone of production. The exploitation of theimmense reserve of variability constituted by the wild diploid cotton species should play a key role to achieve these goals.

This research was conducted to study effect of foliar application of fertilizers on verticillum wilt, yield and yield components of cotton. The research was established in 2004 and 2005 at Karkandeh cotton research station. The experimental design was a randomized complete blocks with factorial arrangement of foliar application of urea and potassium chloride fertilizers in three replications. These Fertilizers were applied as dissolved in water by 0, 5 and 10 kg/ha of urea fertilizer and 0, 5, 7.5 and 10 kg/ha of potassium chloride, respectively. The survey was carried out in two individual experiments by Siokra cultivar (tolerant to verticillum wilt) and Varamin cultivar (sensitive to verticillum wilt). Results showed that years of trial had significantly effect (&#945=0.05%) on verticillum wilt and yield of cotton. Despite potassium chloride fertilizer, foliar application of urea fertilizer decreased percent of verticillum wilt and increased index of verticillum wilt in Siokra, respectively. Yield of Siokra was decreased and increased by foliar application of urea and potassium chloride fertilizers, respectively. In Varamin, percent and index of verticillum wilt were increased and decreased by foliar application of urea and potassium chloride fertilizers, respectively. Interaction effect of foliar application of urea and potassium chloride fertilizers resulted the minimum verticillum wilt index by N5K7.5 and N5K10 treatments and N5k10 treatment in Siokra and Varamin cotton cultivars, respectively.

The art of plant breeding was developed long before the laws of genetics became known. The advent of the principles of genetics at the turn of the last century catalyzed the growth of breeding, making it a science-based technology that has been instrumental in substantial improvements in crop plants. Largely through exploitation of hybrid vigor, grain yields of several cereal crops were substantially increased. Intervarietal and interspecific hybridizations, coupled with appropriate cytogenetic manipulations, proved useful in moving genes for resistance to diseases and insect pests from suitable alien donors into crop cultivars. Plant improvement has been further accelerated by biotechnological tools of gene transfer, to engineer new traits into plants that are very difficult to introduce by traditional breeding. The successful deployment of transgenic approaches to combat insect pests and diseases of important crops like rice (Oryza sativa L.), wheat (Triticum aestivum L.), maize (Zea mays L.), barley (Hordeum vulgare L.), and cotton (Gossypium hirsutum L.) is a remarkable accomplishment. Biofortification of crops constitutes another exciting development in tackling global hunger and malnutrition. Golden Rice, genetically enriched with vitamin A and iron, has, for example, the real potential of saving millions of lives. Yet another exciting application of transgenic technology is in the production of edible vaccines against deadly diseases. How these novel approaches to gene transfer can effectively supplement the conventional breeding programs is described. The current resistance to acceptance of this novel technology should be assessed and overcome so that its full potential in crop improvement can be realized.

Productivity of crops grown for human consumption is at risk due to the incidence of pests, especially weeds, pathogens and animal pests. Crop losses due to these harmful organisms can be substantial and may be prevented, or reduced, by crop protection measures. An overview is given on different types of crop losses as well as on various methods of pest control developed during the last century. Estimates on potential and actual losses despite the current crop protection practices are given for wheat, rice, maize, potatoes, soybeans, and cotton for the period 2001-03 on a regional basis (19 regions) as well as for the global total. Among crops, the total global potential loss due to pests varied from about 50% in wheat to more than 80% in cotton production. The responses are estimated as losses of 26-29% for soybean, wheat and cotton, and 31, 37 and 40% for maize, rice and potatoes, respectively. Overall, weeds produced the highest potential loss (34%), with animal pests and pathogens being less important (losses of 18 and 16%). The efficacy of crop protection was higher in cash crops than in food crops. Weed control can be managed mechanically or chemically, therefore worldwide efficacy was considerably higher than for the control of animal pests or diseases, which rely heavily on synthetic chemicals. Regional differences in efficacy are outlined. Despite a clear increase in pesticide use, crop losses have not significantly decreased during the last 40 years. However, pesticide use has enabled farmers to modify production systems and to increase crop productivity without sustaining the higher losses likely to occur from an increased susceptibility to the damaging effect of pests. The concept of integrated pest/crop management includes a threshold concept for the application of pest control measures and reduction in the amount/frequency of pesticides applied to an economically and ecologically acceptable level. Often minor crop losses are economically acceptable; however, an increase in crop productivity without adequate crop protection does not make sense, because an increase in attainable yields is often associated with an increased vulnerability to damage inflicted by pests.

研究棉花抗枯、黄萎病育种技术，选育棉花抗枯、黄萎病的多抗性新品种。试验采用致病力强的菌种，培养备制成棉枯萎病棉籽粉载菌体和棉黄萎病孢子悬浮液，研究不同菌量、不同接菌方法、致病温度因素、病圃接菌选择及多抗病性育种选择技术指标。播前土壤接棉枯萎病菌棉籽粉载菌体，棉苗2片真叶时，伤根接黄萎病菌孢子悬浮液，盖膜保温诱导发病，淘汰感病群体及感病个体。大田病圃是在重病地接种发病棉杆，移栽时再用棉黄萎病菌孢子悬浮液沾根，发病高峰淘汰棉枯、黄萎病感病群体及感病个体，结合丰产、优质性状的遗传选择，培育出抗病棉花品种。该项技术是在研究棉花苗期诱导抗性和大田病圃筛选相结合构建的新方法。 | The cotton breeding technique resistant to both Fusarium wilt and Verticillium wilt should be studied in order to gain resistant cultivars based on it. The method of inducing cotton multi-resistance by selection with artificial inoculation was adopted in the study. The strong virulence pathogen strains of wilt diseases were cultured in autoclaved cottonseed to make pathogen carrier respectively. Fusarium oxysporum f. sp. Vasinfectum was inoculated with cottonseed meal at the dosage of 90 gand#8226;m-2 in nursery soil before sowing. Then each seedling was inoculated with 10 ml of Verticillium dahliae spore suspension at the concentration of 2×107 spores per milliliter by watering injured roots at 2 true leaf growth stage. The nursery bed was covered with polythene film to keep the average bed temperature of 2025℃. Then the susceptible varieties or plants would show disease symptoms and should be eliminated. And the resistant plants of resistant variety were selected and transplanted to the field which was inoculated with the diseased cotton plant 1500 kgand#8226;ha-1 beforehand. Each seedling was inoculated with Verticillium dahliae spore suspension by dipping injured roots when they were being transplanted. And the susceptible varieties or plants were eliminated again in field. It was shown that this breeding technique was practicable and efficient. The cotton varieties with multi-resistance, good fiber quality and high yield production, were bred in our breeding practice with this technique adopted.

Motes are cotton (Gossypium spp.) ovules that fail to ripen into mature seeds. These aborted ovules represent a loss in yield and can cause imperfections in yarn and cloth quality. The present study was conducted to determine whether 10 widely grown cotton cultivars differ in some boll characters that are undesirable for the textile industry. The bolls at the first positions of fruiting branches formed at 1st (bottom), 6th (middle) and 11th (top) nodes of the main stem were compared in 10 varieties in 2 years for the number of motes and their weights, mote production frequency, and long fibre mote frequency within a boll. Mote frequencies and mote weights were affected by varieties and years. Moreover, mote frequencies were higher at the bottom and middle plant positions compared with the top position. Fibre length for long fibre motes ranged from 18 to 21 mm. In both years, cultivars Deltaopal, Sayar 314 and Suregrow 125 had consistently lower mote and long fibre mote frequencies. Thus, these cultivars could be useful in breeding programmes to improve seed-set. Cotton breeders also need to consider long fibre motes in plant improvement studies.

The defining features of any cropping system are (i) the crop rotation and (ii) the kind or intensity of tillage. The trend worldwide starting in the late 20th century has been (i) to specialize competitively in the production of two, three, a single, or closely related crops such as different market classes of wheat and barley, and (ii) to use direct seeding, also known as no-till, to cut costs and save soil, time, and fuel. The availability of glyphosate- and insect-resistant varieties of soybeans, corn, cotton, and canola has helped greatly to address weed and insect pest pressures favored by direct seeding these crops. However, little has been done through genetics and breeding to address diseases caused by residue- and soil-inhabiting pathogens that remain major obstacles to wider adoption of these potentially more productive and sustainable systems. Instead, the gains have been due largely to innovations in management, including enhancement of root defense by antibiotic-producing rhizosphere-inhabiting bacteria inhibitory to root pathogens. Historically, new varieties have facilitated wider adoption of new management, and changes in management have facilitated wider adoption of new varieties. Although actual yields may be lower in direct-seed compared with conventional cropping systems, largely due to diseases, the yield potential is higher because of more available water and increases in soil organic matter. Achieving the full production potential of these more-sustainable cropping systems must now await the development of varieties adapted to or resistant to the hazards shown to account for the yield depressions associated with direct seeding.