جستجوی مقالات مرتبط با کلیدواژه « تاریخ کاشت » در نشریات گروه « منابع طبیعی »

Quinoa (Chenopodium quinoa wild) is a dicotyledonous plant with about 95% purity. Quinoa is one-year, broad-leaved and has a height of one to two meters. This plant is native to South America, which is generally cultivated for its seeds, but its biomass is also popular as leafy vegetables. The seed of this plant is small in size and is a rich source of many vitamins and proteins. For this reason, its cultivation is expanding in Iran. For this reason, it is very important to know the effects of various factors such as planting method, planting time and cultivar used on its yield and biomass. Due to the high cost of field experiments, the AquaCrop model was used to simulate this crop plant in this research.

The current research was conducted in Khuzestan Agriculture and Natural Resources Research and Training Center located at 31° 20’ N latitude and 48° 40’ E longitude with a height of 18 meters above sea level during the years 2017-2018 and 2018-2019. The ten-year average rainfall leading to the time of the experiment is 240 mm and the average annual temperature is 25.3 degrees Celsius. The experimental treatments include planting dates at four times (T1: October 30, T2: November 10, T3: November 20, and T4: November 30), cultivation methods in two ways (R1: transplanting and R2: seed planting) and three cultivars (C1: Giza, C2: Q26 and C3: Titicaca). Tillage operation was done at the end of May for all treatments.

The sensitivity of the AquaCrop model to changes in base temperature, high temperature and initial canopy cover parameters was in the low category. Due to the low sensitivity of these parameters, the base and high temperature values remained as default. The initial canopy cover was also dependent on plant density, that's why its value was changed compared to the default state. The sensitivity of the AquaCrop model to changes in two parameters of normalized water productivity and the maximum crop coefficient for transpiration was in the high category. The sensitivity of other parameters was in the medium category and therefore these parameters were recalibrated. The average observed and simulated yield differences for T1, T2, T3 and T4 treatments were 198, 153, 97 and 97 kg.ha-1, respectively. The minimum difference between observed and simulated yield values was 93, 78, 62 and 66 kg.ha-1, respectively, and the maximum difference was 303, 210, 172 and 151 kg.ha-1 respectively. Therefore, the accuracy of the AquaCrop model was higher compared to the planting dates in the middle and end of November. The average difference between simulated and observed biomass for planting dates T1, T2, T3 and T4 was 870, 542, 533 and 635 kg.ha-1, respectively. The lowest difference for these treatments was 529, 401, 417 and 324 kg.ha-1 respectively and the highest difference was 1072, 871, 609 and 793 kg.ha-1 respectively. The average observed and simulated yield differences in the two cultivation methods R1 and R2 were 171 and 102 kg.ha-1, respectively. The lowest and the highest difference between the observed and simulated yield was 62 and 303 kg.ha-1 in the germination method and 66 and 194 kg.ha-1 in the direct method. Based on these results, the accuracy of the AquaCrop model in the direct method was about 40% higher than the seed planting. The average difference between the observed and simulated biomass in two germination and direct methods was 723 and 566 kg.ha-1, respectively. The minimum and maximum yield differences in the germination method were 567 and 979 kg.ha-1, respectively, and in the direct method, 324 and 1072 kg.ha-1. The average observed and simulated yield difference for this cultivar was 128, 158 and 123 kg.ha-1, respectively. The lowest observed and simulated yield differences for these three cultivars were 62, 96, and 67 kg.ha-1, respectively, and the highest yield differences were 303, 298, and 291 kg.ha-1, respectively. The average difference between observed and simulated biomass for three varieties of Giza, Q26 and Titicaca was 581, 662 and 691 kg.ha-1, respectively.

Based on all the results, the use of this plant model is suggested for simulating quinoa, although its error is less for direct cultivation in the middle and end of November than other conditions.

In order to investigate the agrophysiological response of cotton to foliar application of stress modulators in different planting date, an experimental was conducted as split-plot factorial in a randomized complete block design with three replications in 2017-2018. Factors were: planting date (early (May 15 and 20, for the first and second year, and late (June 20 and 17, for the first and second year, respectively) as the main plot and type of stress modulator at four levels (control, salicylic acid, glycine betaine and sodium nitroprusside) and time of stress modulators application (flowering and flowering + bolling stage) as a factorial in the sub-plot. Both in early and late planting date, foliar application in flowering+bolling stage increased the number of reproductive branches, number of bolls per plant, seed cotton and lint yield. The highest number of bolls per plant was obtained in early planting date by foliar application of glycine betaine (15.7) and in late planting date by foliar application of salicylic acid (8.7). While salicylic acid foliar application increased the seed cotton yield in early planting date (47%), but in late planting date, seed cotton yield did not respond to the stress moderator application. In both flowering and flowering+bolling stage, the highest seed cotton yield was obtained by spraying sodium nitroprusside (1265 and 1537 kg/ha, respectively). In terms of lint and seed yield, in early planting date, foliar application of sodium nitroprusside and in late planting date, foliar application of salicylic acid was better than other modifiers. Overall, the results of this experiment showed that sowing at the appropriate date and foliar application with salicylic acid in the flowering + bolling stage is the most appropriate treatment to obtain the highest seed cotton yield in saline condition.

This research was done during 2015-2016 as split-plot experiment as RCD with 3 replication in laboratory of Agriculture and Natural Resources Research Center, Zanjan. Sowing date of mother plant as main-plot in 3 levels contained: D1: 7 Oct 2011, 2012 D2: 22 Oct 2011, 2012 D3: 6 Nov 2011, 2012 and 10 cultivars of mother plant included: Opera, Karaj3, KR4, GAo96 × Zarfam (1)(2), Okapi × GAo96 (2)(5), Orient × Modena (2)(4), Orient × Modena (5)(4), Okapi × GAo96 (2)(2), Okapi × GAo96 (5)(2) and GAo96 × Zarfam (5)(1) as sub-plots were considered that conducted in a two year experiments as split-plot as base of RCBD. The studied traits included: germination percent, time required for germination, germination rate, root length, shoot length, seedling dry weight. The result of variance analysis showed that sowing date and cultivar simple effect were significant on mentioned traits. Sowing date and cultivar interaction also was significant effect on mention characteristics. The mean comparison of sowing date and cultivar interaction on germination percent demonstrated that Opera, Okapi x GA096 (5)(2) and GA096 x Zarfam (5)(1) each with mean of 100% had the most germination percent in all sowing date. Generally, results revealed that delaying in sowing date resulted to decreased germination percent. Result showed that cultivars and lines that had the highest germination percent also had the longest root and shoot length.

In order to study the effects of planting date on quantitative and qualitative characteristics of different clover seed varieties, this research was conducted in a field during cropping year of 2012. The research facilities of Seed and Plant Improvement Institute of Karaj use at this study. This research in split plots including the major factor of planting date on 3 cultivation levels (conventional planting date 11 September and delayed planting date including 5 September and 20 October) and the sub-factor clover genotypes at 10 cultivation levels (Persian clover 7 cultivar, Berseem clover (production in Karaj). red clover, a variety called Nasim and Locki clover, a variety called Alborz 1). This research was conducted in a randomized complete block design (RBCD) with four replications. The results showed that the effect of planting date for traits such as grain yield, harvest index and seed quality traits is significant at one percent level. The results seed quality traits showed that the first planting date (11 September) with 86.4 germination percentage and 38.3 germination rate is the best treatment. Comparing the varieties showed that the Persian clover cultivars number 1 with 92.2% germination and 43.8-rate germination is the highest rate. Comparing the mean of varieties showed that the Crimson clover Alborz number 1 seed with 35 grams weight and the harvest index of 4.5 best among the studied varieties

The most important diseases of wheat are yellow rust and Fusarium wheat in the Moghan region. The study was conducted to determine the planting date on the yellow rust disease and Fusarium wheat on yield and yield components of wheat varieties. The experiment lay out as a split plot design in a randomized complete block design (RCBD) withing three replicate in Moghan livestock farming and industry. Planting date treatments includs October 22, November 6 and 21 were allocated to the whole plots. Four and two line of wheat varieties named Bogaru, Pishtaz, Nogal and Shiroudi, N-85-5 and N-80-19 were allocated in the subplot. The following paramiters inclduding grain yield, spike length, spikelet number, seed weight, number of grains per spike, plant height, tiller number, harvest index and coefficient of wheat yellow rust disease progression and disease index of Fusarium were recorded during the growing season. Results showed that different Date were significant on the number of fertile tillers, grain weight per spike, harvest index in the P≥5% and the total length of spike and grain weight per plant at P≥1%. The highest susceptibility to the fusarium diseases was observed on Bogaru variety at the October 22 with 41.66%. The highest susceptibility to fusarium diseases was observed on N-80-19 line at the November 6 with 19.82%. The highest yield was observed on Pishtaz cultivar at November 6. However Nogal can be as tolerant cultivars to yellow rust and Fusarium grown in the region. The best planting date to reduced disases of yellow rust and fusarium of wheat in Moghan were Nov.6 to 21.

In order to consider the effect of sowing date on germination characteristics in seeds of Pinus brutia, a Complete Random block design with four replications and 60 vests per replication was performed and pure seeds of Pinus brutia were planted in two different dates including November 20 and February 1. At the beginning of growth season, germination was recorded every 5 days. Then results of parameters including germination, germination percent, energy, peak value, speed and capacity and survival were calculated in autumn and winter sowing date. The results showed significant effect of sowing date on germination. Suitable sowing date for seeds of Pinus brutia is autumn, which is optimal considering labor force scarcity in winter and decrease in costs.