فهرست مطالب

Journal of Agricultural Science and Technology
Volume:2 Issue: 2, Apr 2000

  • تاریخ انتشار: 1381/05/11
  • تعداد عناوین: 8
|
  • Comparison of Plant Species as Host for Cabbage Leaf Miner in Khuzestan Province
    A.A. Seraj Page 5
    ABSTRACT Cabbage leaf miner Scaptomyza flava (Fallen) (l)iptera: Drosophilidae) is a native and oligophagous leaf miner insect on cruciferous plants (Brassicaceae). It occurs in many parts of the world and throughout Khuzestan. The relationship between feeding and ovipositional preferences of insect, and host plant suitability on seven host plant species (cauliflower Brassica oleracea var. botryds, green cabbage B. oleracea var. capitata, hedge mustard Sisymbrium officinale, brussels sprout B. oleracea var. germmifers, turnip Brassica rapa, cucumber Cucumis mtivits, wheat Triticum aestivum and rice Oryza saliva) was evaluated. Ovipositional preference of 5. flava was determined by measuring feeding punctures and egg density after ndult female flies were given a simultaneous choice and non-choice of all host plants for feeding and oviposition. Studies were performed under greenhouse conditions. The experimental design was a randomized complete block one with 8 treatments and 5 replications of each treatment. S. jlava showed distinct hierarchical ordering in its ovipositional preference, with turnip, green cabbage, and hedge mustard being preferred over all others. Approximately 1.05 and 5.8 times more eggs were deposited on green cabbage than on turnip and cauliflower respectively. When the percentage of punctures with eggs was calculated for each species, cauliflower had by far the highest value at 10% and 19.7% in choice and non-choice tests respectively. For all other species on which eggs were laid it was less than half this. In non-choice tests, females laid more eggs on green cabbage and turnip than other brassicas.
  • Y. Emam, G.R. Moaicd Page 75
    hi a field experiment the effect of five planting densities (100, 175. 250, 325 and 400plants in"uminonion chloride, CCC) on barley (cv Valfajr) was studied. The results indicated that hastened the rate of apical development and stem elongation. This pattern continuedup to the beginning of rapid stem elongation phase (Zadoks growth stage 32).However, during the rapid stem elongation and ear growth, the pattern was reversedi.e. it had become slightly in favor of the lower densities. Increasing plant density upto 25(1 plants in"was no significant change in grain yield. It appeared that the higher plantingdensities, i.e. 250 to 400 plants m~- were in a range around the supposed "optimum"density. Foliar application of CCC slowed down the rate of apical development andstein elongation in all plant densities, hut without any significant effect on its spikeletinitiation rate. Such retardation of development in CCC-treatecl plants was initiallyassociated with lower dry weight accumulation. However, this trend was reversedbefore anthesis, as the CCC- treated plants had accumulated more dry matter by anthesis,and gave a higher grain yield. The interactive effect of CCC and plant density isworthy of further exploration.2) with or without foliar application of chlormequat chloride (2-till o methyltrimethylgrowth, development and grain yield of winterIncreasing plant density2 increased the grain yield, however, from 250 to 400 plants m"2 there
  • J. Asghari Page 85
    Viable pollen grains and eggs are necessary for processes of pollination,fertilization, and embryo formation for seed production. Various staining techniqueswere used to estimate pollen viability in herbicide treated plants. Effect ofmetsulfuron-methyl (2-[in(4-methoxy-6-methyl-l,3,5-triazine-2-yl) amino] carbonyl]amino] siilfonyl] benzoic acid) on pollen grain viability of dyers woad h.) 3,5,8,12 g a.i./ha metsulfuron in mid-anthesis stages. The treated plants wereharvested in 1,3,5,7,9 and 12 day intervals after treatment and compared with controlplants. Aniline blue in lactophenol (acid) and acetocarmine in glycerin (basic) wereused for staining herbicide treated pollen grains. Full staining of dyers woad pollengrains significantly declined as herbicide application rates increased. Postponing thetime of harvest through intervals of several days after treatment decreased the pollengrain stainability, irrespective of herbicide rate. With similar staining trends amongpollen grains with the acidic and basic techniques, a significant difference instainahility rate of the pollen grains was observed, with lower staining rates withaniline blue in lactophenol versus acetociirmine in glycerin. The rate of pollen grainstainability of herbicide treated weeds gave an adequate estimation of viability andfertility of pollen grains. As the percentage of pollen grain stainahility decreased, theefficacy of metsulfuron increased and vice versa. Use of various acidic and basic stainsto estimate pollen viability can be an adequate procedure to determine the treatedherbicide efficacy.(Isatis tinctoriainflorescence was investigated. Pollen grains of these plants were treated with
  • Page 107
    ABSTRACT Tomato spotted wilt virus (TSWV) was detected in tomato leaf and fruit samples collected from Viiramin reyion in Tehran province using indicator test plants including Petunia hybrida, Nicatiana glutinosa, N. tabacum cv. Snmsun NN, N. clevelandit and N. benthamiana and seroloyical tests. Small browinsh local necrotic lesions appeared on P. hybrida leaves 2-4 days post-inoculation. Systemic symptoms included concentric ring spots on leaves, stem necrosis, wilting and tissue collapse of plants 7-10 days following the inoculation. Among 145 tomato samples collected from Ghazvin, Hashtgerd, Karaj, Malard, Shahriar and Varamin in Tehran province, only Varamin samples were infected with TSWV using EL1SA, DIBA and SSEM. TSWV host range specificity and symptom expression were tested on Capsicum annuum L., Chenopodium amaranticolor I«, Citrullus vulgaris L., Oicumis melo var. inodorus, C. mela var. reticukUus, C. salivas L., Lycopersicon esculentum Mill., Phasenlus vulgaris L., Solatium melongena 1- and S. tuberosum. Typical symptoms on these plants included concentric ring spots, chlorosis, vein clearing, tissue necrosis, stunting and local lesion formation. Antiserum prepared against a partially purified TSWV preparation cross-reacted with TSWV-infected tomato samples.
  • H. Saremi, L.W. Burgess Page 119
    ABSTRACT Environmental factors mainly temperature are believed to determine the distribution and population dynamics of Fusarium species in a natural ecosystem. Species may be restricted in their distribution by adaptation to specific sets of soil environmental conditions. Population dynamics of five Fusarium species representative of different climatic conditions were studied at three levels of temperature (13-18 / 19-24 / 25-30°C) and constant water potential (field capacity). Temperature had a significant influence on the population level of all test Fusarium species. Fusarium sambucinum showed noticeable reduction of population at warm temperatures. The population of F. solani and F. compaction were higher at high temperatures. The population of cosmopolitan species, F. equiseli showed little change at all experimental conditions, Fusarium acuminalum did not compete well with other species in this experiment, its population being low at all treatments.
  • A.A. Seraj Page 127
    ABSTRACT Cabbage leaf miner Scaptomyza flava (Fallen) (l)iptera: Drosophilidae) is a native and oligophagous leaf miner insect on cruciferous plants (Brassicaceae). It occurs in many parts of the world and throughout Khuzestan. The relationship between feeding and ovipositional preferences of insect, and host plant suitability on seven host plant species (cauliflower Brassica oleracea var. botryds, green cabbage B. oleracea var. capitata, hedge mustard Sisymbrium officinale, brussels sprout B. oleracea var. germmifers, turnip Brassica rapa, cucumber Cucumis mtivits, wheat Triticum aestivum and rice Oryza saliva) was evaluated. Ovipositional preference of 5. flava was determined by measuring feeding punctures and egg density after ndult female flies were given a simultaneous choice and non-choice of all host plants for feeding and oviposition. Studies were performed under greenhouse conditions. The experimental design was a randomized complete block one with 8 treatments and 5 replications of each treatment. S. jlava showed distinct hierarchical ordering in its ovipositional preference, with turnip, green cabbage, and hedge mustard being preferred over all others. Approximately 1.05 and 5.8 times more eggs were deposited on green cabbage than on turnip and cauliflower respectively. When the percentage of punctures with eggs was calculated for each species, cauliflower had by far the highest value at 10% and 19.7% in choice and non-choice tests respectively. For all other species on which eggs were laid it was less than half this. In non-choice tests, females laid more eggs on green cabbage and turnip than other brassicas.
  • A.H. Ali Baygi, K. Zaralshani, M. Chizari Page 137
    ABSTRACT The purpose of the study was to identify and prioritize the educational needs and support needed by agricultural extension agents in Isfahan, Islamic Republic of Iran. The target population for the study consisted of S3 agricultural extension agents in Isfahan province. Census population were used therefore, sampling procedures were not utilized and genera I izability of the results was limited to study population. Results indicate the five most highly ranked items on educational needs of extension agents were: extension philosophy, instructional technology, innovation and adoption process, adult education, and extension methods. Respondents indicated that the major support needed were availability of subject matter specialists to help them with their technical and communication methods.
  • P. Irani Page 143
    ABSTRACT To evaluate durum pasta quality traits, using international standards, a study was conducted on seven improved and local durum wheat varieties. The traits examined included grain vitreousity (I.CC. No. 129), grain hardness index (h.i.), yellow berry (y.b.(, black point (h.p.), hectoliter weight (h.l.w.), thousand kerne! weight (t.k-w.j, protein percentage (I.CC. No. 105.1), protein quality through sedimentation test (I.CC. No. 116), and wet gluten percentage. Durum wheat gluten quality can be used to detect varieties with favorable traits for pasta making:, some of these traits being: semolina percentage, pigment content, reaction to cooking and pasta disk pressure tolerance. The varieties Zardak from Kermanshah, Altar 84 from Ahwaz and Yavaros 79 from Karaj exhibited the most favorable pasta quality traits. There existed significant positive correlations (at 1% level) between protein percentage and sedimentation test, wet gluten percentage and protein, wet gluten and sedimentation test, and protein percent and dry gluten. The results indicated that protein percentage of durum wheat varieties can be used to select varieties of favorable quality for pasta making.