2nd Sowing Research Articles

Effect of Seed Rates and Sowing Dates on Productivity of Wheat (Triticum aestivum L.)

A field experiment was conducted at the Agronomy farm of Nepal Agricultural Research Council (NARC), Khumaltar, Lalitpur to evaluate the effect of sowing dates and seed rates on yield and yield attributes of wheat. The experiment was laid in a split-plot design with three replications treated with 4 sowing dates as the main plot factor (12th Nov, 27th Nov, 12th Dec, and 27th Dec) and 4 seed rates as subplot factor (100 kg ha-1, 120 kg ha-1, 140 kg ha-1 and 160 kg ha-1). Results revealed that the leaf area index was significantly affected by sowing dates and was comparatively superior in 2nd sowing date (27th Nov) wheat. Similarly, in the case of seed rates, the leaf area index was influenced significantly and was recorded to be increasing with an increase in seed rates. Phenological parameters like days to 50% heading, flowering, and maturity were observed maximum (116, 123, and 179 days, respectively) in early sown wheat and reduced with the subsequent delay in sowing. Maximum values of yield and yield attributes like effective tillers per meter square (635.6), spike length (9.56 cm), grains per spike (41.49), grain yield (7.59 Mt ha-1), and straw yield (9.58 Mt ha-1) were observed in the wheat sown in 2nd date (on 27th Nov) which differed significantly to wheat sown on other dates. Seed rates had no significant influence on grain yield and yield attributes. Thousand-grain weight was found maximum (46.26 g) in early sown wheat (on 12th Nov sown wheat, reduced with the subsequent delay in sowing, and the harvest index was observed as maximum (0.51) under December 27 sown wheat. Though the yield and its attributes were not influenced significantly by seed rate, the maximum yield (6.18 Mt ha-1) was observed in wheat sown at the rate of 120 kg ha-1. Considering seed yield and its parameters, 2nd date of sowing wheat (27th Nov) and seed rate of 100 kg ha-1 could be the best option to uplift the productivity of wheat in rainfed lowland conditions of Lalitpur, Nepal.

RESULTS OF THE RESEARCH ON THE INFLUENCE OF SOWING DATE ON THE CHEMICAL COMPOSITION OF MAIZE GRAIN AT R.D.S.C.B TG. MUREŞ

Climate changes, more prominently visible in recent years, have alerted scientific research and, implicitly, the agricultural sector, which is most affected by these changes. Maize, is one of the most widespread field crops in our country, is also the most exposed to atmospheric and soil drought pronounced in the summer months. In this context, we initiated and tested the following experimental variants: earlier sowing, when in the soil, at a depth of 10 cm, 6 °C is achieved, sowing in the optimal period, at 10°C in the soil and sowing after the optimal period, following the evolution of both American and Romanian hybrids. The temperature evolution during the vegetation period of the crop, in the three years of the study, did not show significant differences, the influence on the change in the chemical composition of the grains was not obvious. The evolution of precipitation was fluctuating over months and years. The studies focused on the influence of the sowing season on the production and quality of corn grains in the area of the Research and Development Station for Cattle Breeding Târgu Mureș (RDSB Târgu Mureș). According to the data recorded in the 2018-2020 agricultural years, in the geopedological conditions of the Sângeorgiu de Mureș area, the studied hybrids responded well to early sowing, and the composition of the grains did not register substantial changes. The polyfactorial experiment was realized in the years 2018, 2019 and 2020 in the experimental field of the Plant Laboratory at RDSCB Târgu Mureș, according to the method of subdivided plots, the first factor the sowing date, with 3 gradations: the first sowing date, an early sowing was realised when 6ºC were recorded in the soil; the 2nd sowing date, an optimal sowing date when 10ºC was achieved in the soil and the 3rd sowing date, two weeks after the 2nd. Factor 2 is represented by the 4 tested corn hybrids.

ADAPTIVE POTENTIAL OF FENUGREEK SPECIES AT DIFFERENT SOWING TIMES

Among the unexplored technological elements of growing fenugreek in the conditions of Ukraine is the creation of conveyor cultivation of the culture. Therefore, the problem of the influence of sowing dates on the growth and development of plants, the parameters of the harvest and the qualitative composition of marketable products is acute. The purpose of this study was to substantiate the optimal sowing dates of fenugreek species to increase the yield of dried products in the conditions of Polissia on sod-podzolic soils. The leading methods employed to investigate this issue were the field method – to find the interaction of the object of research with biotic and abiotic factors, statistical method – to evaluate the research results to find the parameters of fenugreek’s adaptive capacity. During 2012-2014, for different sowing periods, the average yield of dry mass in blue fenugreek varied from 0.5 to 1.3 t/ha, and in hay fenugreek – from 0.6 to 1.5 t/ha. The early spring period and the late spring period of the 1st sowing period were characterized by the highest overall adaptive capacity. The highest value of the specific adaptive capacity was established during the late spring 2nd sowing period. The relative stability index ranged from 2.6 to 11.4. Blue fenugreek during the late spring 1st and 2nd sowing periods responds well to improved growing conditions (bi >1), and fenugreek hay during the late spring 2nd and summer sowing periods. Early spring and late spring 1st sowing period samples are characterized by high breeding value. An increase in the sum of effective temperatures by 1°C contributed to the fluctuation of green mass yield from 4.82 to 128 kg/ha, and dry mass yield from 0.401 to 6.63 kg/ha. At the same time, an increase in precipitation by 1 mm affected the fluctuation of the yield of green mass from 15.0 to 146 kg/ha, and of dry mass from 0.145 to 25.9 kg/ha. Commercial production of fenugreek species was formed within the range of the sum of air temperatures (>10°C) 383.9-487.1°C, the amount of precipitation 70.7-144.3 mm, and the growing season ranged from 35 to 55 days. The highest productivity of fenugreek species was found during sowing from the second decade of April to the first decade of May. The materials of this paper are of practical value for expanding the species diversity of vegetables and increasing the supply of the population with valuable food products and during the application of new and improved elements of technologies for growing valuable rare crops to achieve the maximum effect of fulfilling the genetic potential of plants

EFFECT OF SOWING DATE ON SOME AGRONOMIC AND TECHNOLOGICAL TRAITS OF SAFFLOWER (Carthamus tinctorius L.) IN NORTHERN TURKEY

This research was determined the effect of sowing dates on some agronomic and technological characters of safflower cultivars. The research was conducted in Samsun during the season 2017-2019 using 4 sowing dates (30 October, 14 November, 29 November and 14 December) and two safflower cultivars (Olas and Linas). The result of research, plant height 82.3-158.7 cm, the number of head 4.15 to 9.47 head-1 plant, seed weight per head 0.84 to 1.39 g, thousand seed weight 34.65 to 47.69 g, seed yield per plant 3.14 to 7.67 g, oil content 24.64 to 29.29% and oil yield per plant 0.83 to 2.25 g were determined. The result of interaction between sowing date and variety showed that for Olas variety the highest agronomic and technological traits were obtained in the 2nd sowing date, for Linas variety the highest values except for plant height and thousand seed yield were obtained in the 2nd sowing date. In addition, it was concluded that the second sowing date (14 November) is more suitable for safflower cultivation in the winter season in Samsun ecological conditions.

Growth, yield and quality of two guar (Cyamopsis tetragonoloba L.) ecotypes affected by sowing date and planting density in a semi-arid area.

The growth period, phenology, grain yield and gum content of two different guar ecotypes were studied in response to different sowing dates and plant densities. A two-year field experiment was conducted as a split-factorial in a randomized complete block design (RCBD) with three replicates in the research field of Tarbiat Modares University during 2016 and 2017 growing season. Main plots consisted of four sowing dates (May 21, June 4, June 21 and July 5 in 2016 and May 10, May 26, June 10 and June 26 in 2017), and subplots including three plant densities (13, 20 and 40 plants m-2) and two ecotypes (Pakistani and Indian). Based on findings, the phenological traits, plant height, grain yield and harvest index were significantly affected by plant density. The effect of ecotypes was statistically significant (p<0.05) on all traits except harvest index in the first year. Furthermore, the seed sowings on May 21 and May 26 with 13 plants m-2 led to highest grain yield (3004.8 and 2826.10 kg.ha-1 for two consecutive years). The high gum content (33.68 and 33.78% for two consecutive years) was also recorded for Pakistani ecotype while for gravity, Indian ecotype showed higher value in both crop years. By and large, the Pakistani ecotype showed better response compared to the Indian one in both years, especially in 1st and 2nd sowing dates.

Siirt Ekolojik Koşullarında Ekmeklik ve Makarnalık Buğdayda Uygun Ekim Zamanının Belirlenmesi

Bu çalışma Siirt ekolojik koşullarında ekmeklik ve makarnalık buğday çeşitlerinde uygun ekim zamanını belirlemek amacıyla 2015-2016 yetiştirme sezonunda yürütülmüştür. Araştırma materyali olarak bölgede yoğun olarak yetiştiriciliği yapılan ekmeklik buğday (Ceyhan 99) ve makarnalık buğday (Artuklu) çeşitleri kullanılarak, 5 farklı zamanda (1 Ekim, 15 Ekim, 1 Kasım, 15 Kasım ve 25 Kasım) ekim yapılmıştır. Çalışmada bitki boyu, başak Boyu, metrekaredeki başak sayısı, başakta tane Sayısı, bin tane ağırlığı, biyolojik verim, tane verimi, hasat indeksi, kardeş sayısı,10 başak ağırlığı ve hektolitre ağırlığı incelenmiştir. Elde edilen verilere göre incelenen kriterler arasında bulunan bitki boyu, başak boyu, bardeş bayısı, betrekaredeki başak sayısı, başakçık sayısı, başakta tane sayısı, bin tane ağırlığı ve biyolojik verim değerleri arasinda istatistiksel olarak önemli farklar bulunmuştur. İncelenen karakterler arasında en yüksek tane verimi değeri Artuklu buğday çeşidinde II. ekim zamanında 908.97 kg/da ve Ceyhan 99 buğday çeşidinden III. ekim zamanından 866.00 kg/da olarak elde edilmiştir. Bu araştırma sonucunda Siirt ekolojik koşullarında en uygun ekim zamanının ekmeklik buğdayda 28 Ekim; makarnalık buğdayda ise 14 Ekim tarihinde olduğu ortaya konulmuştur.

Evaluation of Some Faba Bean Genotypes Under Three Planting Dates in Middle Egypt

The recent work was conducted in the Agricultural Research Stations of Mallawy, El-Minia Governorate and Sids, Beni-Suif Governorate, Egypt, during two successive winter seasons of 2016/2017 and 2017/2018 to study the effect of sowing date on productivity of eight faba bean genotypes, (Sakha-1, Sakha-3, Giza-843, Giza-716, Pop.-10, SB-1, BF-10 and Sids-19). Three sowing dates (October 15th, November 1st and November 15th) were used. The results of the combined analysis of the two growing seasons 2016/2017 and 2017/2018 showed that, number of days to both flowering and maturity and number of branches were significantly affected by sowing date. The productivity traits were significantly affected by sowing date, specially, seed yield per faddan. The results revealed significant differences among the eight faba bean genotypes in their performance in both of number of days to flowering and maturity. The earliest faba bean genotypes were Giza-843, Sakha-3 and Giza-716 in both Sids and Mallawy. It was found that, late sowing showed a shorter period until to maturity. Genotypes produced higher seed yield/plant at the 2nd sowing date (November 1st). Genotypes produced heaviest 100-seeds in the 1st sowing date, because, plants stayed longer to reach maturity, relative to those planted in both of Novamber1st or November 15th, since seeds given much time to grow. Sakha-3 in both Mallawy and Sids, attained the highest seed yield (tonfad.). The second sowing date (November 1st) was most proper and any of Sakha-1 and Sakha-3 Sids-19 might be adopted to Middle Egypt.

Effect of weather parameters and date of sowing on intensity of Alternaria blight of rapeseed mustard

The production and productivity of oilseed brassicas are revelation to the biotic and abiotic stresses that divulges to lower the world average. The Alternaria blight disease severity is confided to weather conditions, varieties, age of host plants and the pathogens. Experiment was set up, to analyze the effect of weather variable and sowing dates on the disease severity of rapeseed mustard and its effect on yield. The data for the Rabi season (2017–2018) shown that the periodical increase in the disease severity with the delay in sowing. Percent diseases intensity (PDI) progression was higher during 3rd sowing (D3) at 75 and 100 Days after sowing in Brassica juncea varieties followed by Brassica napus and Brassica nigra varieties. The disease severity differed significantly among the sowing dates and varieties, RLC-3 showed maximum PDI (52.19%) whereas, PC-6 indicated minimum PDI (0.98%).The maximum seed yield (20.37 q/ha) was recorded on 1st sowing (D1) followed by 2nd sowing (D2) (12.59 q/ha). Giriraj showed maximum seed yield followed by GSC-7. Highest Area under disease progressive curve value was recorded in RLC-3 variety (3885.91) having 3rd sowing (D3) and the lowest was recorded in PC-6 variety (54.77) having 1st sowing (D1). The maximum temperature (15.7–30.3 °C) and minimum temperature (3.3–12.6 °C) was positively correlated with disease severity, disease severity increases with increase in temperature and vice versa.

Effect of Different Sowing Dates for the Management of Chilli Pests

The field experiment was conducted at Spices Research Centre, Shibganj, Bogra, Bangladesh during Rabi season of 2015-16 to assess the effect of varying sowing dates against insect pest of chilli. The treatments were T1= 30 August (1st sowing); T2= 15 September (2nd sowing); T3= 30 September (3rd sowing); T4= 15 October (4th sowing), T5= 30 October (5th sowing) and T6= 15 November (6th sowing). Sowing was done at 15 days interval from August to November in the experimental field. The results showed that the maximum mean aphid (9.27/leaf), thrips (10.77/leaf), mite(11.51/leaf) and fruit borer population like H. armigera and S.litura larvae (8.25 and 6.74/plant, respectively) were found in 15 November sowing and minimum number of those insect pest were present in 30 August sowing. Red ripe chilli yields were also found to differ in descending order as follows: 30 August (13.05 t/ha)&gt; 15 September (12.70 t/ha)&gt; 30 September (10.30 t/ha)&gt; 15 October (8.41 t/ha)&gt; 30 October (5.20 t/ha)&gt; 15 November (3.10 t/ha). It was inferred that early sowing (30 August or 15 September) resulted in lower incidence of aphids, thrips, mite and fruit borer. Such low level of insect pest caused less crop injury which resulted in enhancing the red ripe yield of chilli. So, it is suggested that for early sowing of winter chilli, the appropriate planting time may be 30 August to 15 September.&#x0D;

Influence of nitrogen fertilization on formation of productivity elements of facultative triticale when late autumn sowing in the conditions of the Right-Bank Forest-Steppe

Purpose. To establish peculiarities of organogenesis and productivity of facultative triticale under late autumn sowing terms depending on nitrate fertilizations. Methods. The study was carried out in 2016–2018 in stationary field experiment at the farm “Rasavske” (Kaharlyk district of Kyiv region). The influence of autumn sowing terms and nitrate fertilizing on plant productivity elements of the facultative triticale variety Pidzymok kharkivskyi was studied by conventional methods. To evaluate biological features of development of facultative triticale depending on the factors studied the plants on initial stages of organogenesis were taken and microscopic analysis of their apical сones was conducted. Results. In spring 2017, plants of facultative triticale Pidzymok kharkivskyi of the 2nd sowing term were on the I organogenesis stage only, because the emergence has revealed itself under snow during winter. In 2017, 2018 in the II, III and IV organogenesis stages in variants with nitrogen fertilizing there was a tendency to decrease the necessary sum of active temperatures as compared to the control. During the years of the research, the III organogenesis stage continued 7–10 days, but plants formed more spikelet primordia of the ear in year with early spring restoration of the vegetation than on late restoration. Nitrogen fertilization significantly contributed to increase spikelet number per spike of the main stem, especially in the variants of the first sowing term (October, 15). Grain number per spikelet has less correlation with spikelet number per spike thus indicating unused potential of ear. Duration of forming all organs of ear was 27–32 days in the year with early spring restoration of the vegetation (2017) and 19–24 days in the year with late restoration (2018). Conclusions. Late sowing terms and conditions prior to overwintering did not significant effect on facultative triticale overwintering, but its performance was limited by weather factors during the second half vegetation. The weather conditions of the initial periods of vegetation and nitrogen fertilization influenced on spikelet number per spike, and the realization of ear potential (grain number) was 64–75 % of number of fertile flowers in the less favorable 2017 and 75.0–92.4 % in the more favorable 2018.

Nitrogen application and sowing date affect okra pod and seed characteristics

ABSTRACTThe effect of nitrogen (N) application rate and sowing date on seed quality and pod production of four cultivars of okra (Abelmoschus esculentus L.) were examined. Seeds of four okra cultivars (cv. ‘Boyatiou’, ‘Veloudo’, ‘Clemson’, and ‘Pylaias’) were sown on 13 May (1st sowing) and 2 June (2nd sowing). Plants were subjected to three N levels: F1, F2, and F3 (150, 300, and 450 mg N L−1). The 2nd sowing improved flower induction and pod set, without however affecting pod size. The number of seeds per pod was not affected by sowing time, but the mean 100 seed weight was generally lower in the 2nd sowing. In all cultivars, except cv. ‘Veloudo’ germination increased in the 2nd sowing mainly as a result of lower seed hardness. Germination was also improved by increasing N levels, or by seed storage, acid scarification, or seed priming.

The influence of hybrids and sowing term on yield and dry down of corn grain

The dry down rate of corn grain during maturation is influenced by a large number of environmental factors and properties of hybrids, and has a major effect on corn, reaching its full maturity. This is especially important for the timely soil tillage and planting of the next culture. The aim of this research was to determine the yield and dry down rate from corn grains depending on the hybrid and the sowing term, in the agro ecological conditions of South Serbia (Leskovac). For this purpose, an experiment was made during 2016 and 2017 on the territory of the municipality of Leskovac. Soil type was alluvium. The trial was planned according to the schedule of divided land plots, set up in three repetitions. This included 6 hybrids of different FAO maturity groups and three differing sowing terms. The results of the study show that the average content of water in the grain in physiological and technological maturity, at all the hybrids and sowing terms were in 2016 significantly lower than in 2017. The highest average yields in 2016 were achieved with hybrids of the FAO maturity group 600, in the 2nd and 3rd sowing term, while in 2017, the highest yields were recorded with hybrids of the FAO maturity group 500, during the 1st and 2nd sowing term. The average rate of dry down in 2016, in all hybrids, was the highest recorded in the 1st sowing term, and in the year 2017, in 2nd and 3rd sowing term. The most intense dry down rate period in both years, at the hybrids of the FAO maturity group 400 was in the second and third week of physiological maturity, while in FAO maturity hybrids groups 500 and 600 in the third and fourth week of physiological maturity.

Formation of lentil yield components as affected by sowing timing, micronutrients and growth regulators

Purpose. To investigate the influence of sowing timing, microfertilizers and growth regulators on the formation of the components of the lentil ‘Linza’ yield structure.Methods. Field, laboratory.Results. The indices of plant height, height of attachment of the lower bean, number of main stems and stems of 2–3rd order, number of knots on lentil plants, buds, flowers and beans with seeds are given. The total number of seeds from one plant and per bean, the weight of seeds per plant and 1000-seed weight as affected by the factors of the experiment were determined. It has been established that the yield of a crop depends on a number of structural parameters that are being formed at earlier stages of plant growth and development. Having considered the limits of the variation of the yield components, it is possible to some extent agrotechnically neutralize the negative influence of a factor in the process of lentil cultivation. The results of the study of the effect of microfertilizers, growth regulators and their combination on the formation of elements of lentil ‘Linza’ yield structure, both individually and on average, are presented. It has been determined that in all years of the experiment, in terms of most indicators, the highest values of the yield components were recorded in 2016. The best values of the indices under study were obtained in the treatments with the combination of microfertilizer Reakom-SR-Bobovi and growth regulator Stympo at the first sowing date and micronutrient Reakom-SR-Bobovi at the second one.Conclusions. The following combinations of formulations had a better effect on the formation of some indicators of the crop yield: Kvantum-Bobovi on 1000-seed weight, Reakom-SR-Bobovi on the weight of seeds per one plant and Reakom-SR-Bobovi + Stympo on the number of beans, and seeds from one plant at the first sowing date. The application of Reakom-SR-Bobovi increases the total number of beans and set beans, the number of seeds per plant and the weight of seeds per plant; the option of using Reakom-SR-Bobovi + Regoplant positively affects the formation of 1000-seed weight at the 2nd sowing date.

Effect of sowing date on quality seed production of sweet pepper in Bangladesh

A field experiment was conducted to study the effect of sowing date on quality seed production of sweet pepper at the research farm of Seed Technology Division, Bangladesh Agricultural Research Institute, Gazipur, during 2011-2012. The aim of this study was to find out the optimum sowing date for quality seed production of sweet pepper. The treatments were 4 four sowing dates viz. 15 October, 30 October, 15 November and 30 November. Seeds were sown in seed bed for 1st sowing on 30 September, for 2nd sowing on 15 October, for 3rd sowing on 30 October and for 4th sowing on 15 November. The experiment was laid out in randomized complete block design (RCB) with three replications. The highest individual fruit weight, 1000 seed weight was obtained from the October 15 sowing date in the year of 2011-2012 and it was significantly different from all other dates of sowing. Maximum seed yield (86.2 kg ha-1) was recorded in 2nd sowing date (15 October) followed by 3rd sowing date (30 October) treatment while the lowest was found from 4th sowing date (15 November) (30.72, kg ha-1). Maximum seed quality as measured by moisture content, dry weight, vigour index and germination percentage were obtained at different sowing date. Maximum seed weight (mass maturity) was achieved at 1st sowing when average seed moisture contents were 5% and 4%, respectively. For high seed quality, sweet pepper is better sowing time at 2nd sowing time (15 October) which could be regarded as the point of physiological maturity.Progressive Agriculture 28 (3): 216-221, 2017

Impact of Sowing Interval on the Yield and Yield Contributing Traits of Sesame (Sesamum indicum L.) under the Tropical Circumstance

Abstract The experiment was conducted to study the impact of sowing interval on the yield and yield contributing traits of sesame (Sesamum indicum L.), under the tropical circumstance, during 2016, at the research area present near Faculty of Agriculture, Lasbela University of Agriculture, Water and Marine Science, Uthal, Balochistan. Experimental treatments were comprising three varieties of sesame, SV1 (TS-5), SV2 (TH-6) and SV3 (4002), and cultivated under different three sowing dates, at 15 days interval: S1 = 1st sowing (15 March 2016), S2 = 2nd sowing (1st April 2016) and S3 =3rd sowing (15 April 2016). The results of various observations, i.e. plant height at maturity (cm), 1000-seed weight (g), seed mass (t ha−1), yield index (%) rooting depth (cm) and root weight per plant was found to be significant both for the all the sowing dates and sesame genotypes. Non significant finding was observed in traits of biological yield per plant (g) and root-shoot ratio. Whereas interaction among all the treatment factors was non-significant. Maximum yield and yields contributing parameters was observed in S3 = 3rd sowing (15 April 2016) and sesame genotype SV1 (TS-5), followed by SV2 (TH-6), while minimum yield was noted in S3 = 3rd sowing (15 April 2016) and SV3 (4002) sesame genotypes. On the basis of the coastal agroclimatic condition of district Lasbela, it was concluded that maximum yield production was achieved from the sesame variety (TS-5), as compared to other two sesame (TH-6 and 4002) varieties. Sowing date of sesame at 15th April 2016 was more productive, as compared to the other sowing interval. Coastal climatic condition is feasible for sesame cultivation, especially for the sesame variety (TS-5).

Performance of Wheat as Affected by Different Irrigation Levels and Sowing Dates

The experiment was conducted to determine the effect of irrigations and sowing dates on growth and yield performance of wheat in the experimental field of Sher-e-Bangla Agricultural University, Dhaka, Bangladesh during the period of November 18, 2012 to March 30, 2013. The experiment was comprised of two factors, viz. factor A: two irrigations namely irrigation (I) and no irrigation i.e. control (I0), and factor B: three sowing dates such as S1: 1st sowing on 18 November, S2: 2nd sowing on 03 December and S3: 3rd sowing on 18 December. The experiment was laid out in a split plot design with three replications. Irrigation was assigned in the main plot, while sowing time was in the sub-plots. Data on grain yield and different yield contributing characters were taken after harvest. Results indicated that the highest grain yield was obtained with I (2.915 t ha-1) and S1 (2.983 t ha-1). The interaction of irrigation (I) and sowing on 18 November (S1) showed the maximum yield (3.387t ha-1), spike length (17.08 cm), 1000 grain weight (43.4 g), spikelets spike-1 (20.03) and grain spike-1 (65.58) of wheat.The Agriculturists 2016; 14(2) 77-85

Combination of sowing date with deficit irrigation for improving the profitability of carrot in a tropical environment (Brazil)

This study was conducted to determine the most suitable irrigation strategy for improving the water productivity of carrot in Rio de Janeiro (Brazil) by using two sowing dates (June 16th and August 3rd). Experimental data from a two-year field test were used for calibration (2010) and validation (2011) of the simulation of carrot with the MOPECO model under deficit irrigation conditions. In 2010 and 2011 for no-deficit conditions the net irrigation was around 150 and 180mm in the 1st and 2nd sowing date, respectively. The maximum yield was about 64,000kgha−1. The root mean square error (2790 and 2968kgha−1) and the relative error (5.3 and 4.9%) values show good fit between the simulated and observed treatments for 2010 and 2011, respectively. Depending on the water stress target, the use of the optimized regulated deficit irrigation in the study area would increase carrot yield by up to 7% and 15% compared with the a constant deficit irrigation strategy for the two proposed sowing dates under the climatic conditions of 2012. In economic terms, the gross margin reached 6849 and 5881€ha−1 for the first and second sowing dates, respectively.

Effect of sowing date and seeding rate on bread wheat yield and test weight&lt;br&gt;under Mediterranean conditions

Yield and test weight are attributes of particular economic importance in wheat production systems and are strongly affected by environmental conditions. This study was conducted to determine the effects of sowing date and seeding rate on grain yield and test weight of fifteen bread wheat varieties and five advanced lines from Portuguese Wheat Breeding Program (Plant Breeding Station, Elvas, Portugal) under irrigated Mediterranean systems. Field experiments were conducted at two locations of Southeast Portugal, during 2011/2012 growing season. Two seeding rates were compared (200 and 350 seeds.m?2) in two different sowing dates in each location. Results showed that sowing date and seeding rate affects yield and test weight under irrigation field conditions, for Mediterranean region of Southeast Portugal, but only sowing date had significant effects among the varieties. At Elvas, higher yield was obtained with the 2nd sowing date (21 December) for most of the varieties studied. In opposite, in Beja trials, the highest values for yield were found when varieties were sown earlier (1st sowing date - 26 October). Test weight had a similar performance in the two sites, though top values for this trait were found with the 1st sowing date. Comparing the results obtained in the two studied locations, Beja showed, for the majority of the varieties, 3t/ha higher average yield than El

Seedling emergence response to early sowings in unprimed and osmoprimed seeds of fiber sorghums for energy biomass under semi-arid climate

Fiber sorghum is a promising industrial crop for lignocellulosic biomass to be used for energy purposes. Limits to the adoption of early sowings (March-April) for this species are found in its thermal requirements for seed germination (&gt;10°C). Seed osmopriming has been found to decrease the impact of low temperatures on seed germination of sorghum in laboratory. In this study, unprimed (UP) and primed (P) seed germination behavior in both laboratory at cold temperatures and open field conditions under early sowing in a typically Mediterranean environment, was examined in four cold-tolerant cultivars of fiber sorghum (Padana 4, PR 811F, Jumbo and PSE 24213). Seed germination in UP at 8°C was on average 82.4%, confirming the high cold-tolerance of all cultivars selected for the experiment. Germination was progressively delayed by the lowering of temperature from 25°C to 8°C. Seed osmopriming was effective in promoting germination speed at all temperatures in laboratory. It also resulted in an appreciable lowering of thermal time requirements for final germination. With the earliest planting date (March 10), minimum soil temperatures during the first ten days never dropped below 10.2°C, allowing a final seedling emergence of 79.2% in UP. However, low soil temperatures slowed down the rate of seed germination. At the 2nd sowing (end of March), daily maximum temperatures of soil exceeded 20°C but those minimum dropped below 10°C, slightly depressing seed germination in UP (76.3%). With the latest sowings (mid-April and early May), minimum soil temperatures always over exceeded minimum threshold for seed germination, allowing a regular seed germination in UP. Priming increased final emergence percentage in the two earliest sowings (those of March), whilst it enhanced the germination speed in all planting dates. Seed osmopriming also reduced thermal time requirements until the first seedling emerged from soil and promoted the seedling growth in all cultivars and sowing dates. These results suggest that it is possible to adopt early sowings (March) in cold-tolerant cultivars of sorghum under semi-arid climate, and that osmopriming allows the seed to partially overcome the limit imposed by cold soil to germination, contributing to a successful crop establishment when early plantings are adopted. Although the germination response to constant low temperatures in laboratory tests does not always provide a good index for predicting seedling emergence in soil under fluctuating uncontrolled temperatures, it may contribute to define desirable attributes for the identification of cultivars adapt to early sowings in the Mediterranean areas.

Modeling the effect of planting date on Maize (Zea mays L.) crop in Sabour region of Bihar using DSSATv3.5 crop simulation model

CERES-Maize model calibrated for local conditions of Sabour has been used to evaluate the relevance medium range weather forecast relative to the maize crop growth period. The procedure is to place the reference year's daily weather into the model up to the time the yield prediction is to be made and sequences of historical data (one sequence per year) after that time until the end of growing season to give yield estimates. A procedure that makes use of historical weather data, medium range weather forecast (mrwf) and current weather data in conjunction with the CERES-Maize model was developed to arrive at a probable distribution of predicted yields. The lower temperature and more solar radiation in tassel emergence to dough stage silk emergence to physiological maturity phase and lower maximum temperature are found favorable to contribute more in increasing the grain yields. The CERES- Maize model correlated for the genetic coefficient predicts the silking dates and physiological maturity very well. Kharif maize gave the highest grain yield of 3490 kg/ha in 1999 and the lowest of 2474 kg/ha in 1979. Among eight different sowing dates the lowest average grain yield was 3190 kg/ha for the last sowing date and the highest average grain yield was 3313 kg/ha in 2nd sowing date. The 25 percentiles were less than the mean grain yields and also 75 percentiles.&#x0D;