scholarly journals Analysis of self-fertilization and meiotic behavior of eleven Brazilian triticale cultivars at two sowing dates

2011 ◽  
Vol 11 (2) ◽  
pp. 114-124 ◽  
Author(s):  
Divanilde Guerra ◽  
Marcelo Teixeira Pacheco ◽  
Luiz Carlos Federizzi
Keyword(s):  
Pollen Viability ◽  
Sowing Date ◽  
Meiotic Behavior ◽  
Hexaploid Triticale ◽  
Breeding Programs ◽  
Normal Cells ◽  
Meiotic Analysis ◽  
Mean Values ◽  
Sowing Dates ◽  
Self Fertilization

Eleven Brazilian hexaploid triticale cultivars (2n = 6x = 42), from three breeding programs, were evaluated for their ability of self-fertilization in 2006 and for meiotic behavior, meiotic index and pollen viability at two sowing dates in 2007. High potential of self-fertilization was observed, with values up to 89.52 %. Many irregularities were found in the meiotic analysis, such as the presence of univalents, laggard chromosomes and micronuclei in tetrads, which compromised both meiotic behavior and meiotic index. At the first sowing date, more suitable for normal plant development, overall mean values of 52.68 % for normal cells and 64.95 % for meiotic index were observed. At the second sowing date, less appropriate for the crop, overall means of 52.23 % for normal cells and 58.24 % for meiotic index were obtained. Despite all the irregularities, considerable pollen viability was observed, reaching overall means of 92.08 % and 91.07 % for the first and second sowing dates, respectively.

scholarly journals Meiotic behavior of wild Caricaceae species potentially suitable for papaya improvement

2012 ◽  
Vol 12 (1) ◽  
pp. 52-59 ◽  
Author(s):  
Emanuelli Narducci da Silva ◽  
Monique Freitas Neto ◽  
Telma N. S. Pereira ◽  
Messias G. Pereira
Keyword(s):  
Wild Species ◽  
Significant Variation ◽  
Pollen Viability ◽  
Meiotic Behavior ◽  
Breeding Programs ◽  
Meiotic Analysis ◽  
Spindle Fibers

The purpose of this study was to evaluate the meiotic behavior and determine the meiotic index and pollen viability of representative plants of the wild species V. goudotiana, V. quercifolia and J. spinosa. Meiotic analysis confirmed that the species are diploid and have 18 chromosomes. Meiosis was partially normal, since some abnormalities, e.g, sticky and lagging chromosomes, precocious segregation, lack of synchrony, and disturbances in the spindle fibers were observed. These abnormalities resulted in post-meiotic products (monads, dyads, triads, and polyads) that probably contributed to the meiotic index of 85.7 % (V. goudotiana) to 95.9 % (J. spinosa); significant variation was observed in the species V. goudotiana. The pollen viability of 68.0 % (V. goudotiana) to 96.0 % (J. spinosa) was reasonably good in these wild species. Crossings in breeding programs involving V. goudotiana should therefore be carefully planned, since part of the gametes of this species is unviable.

scholarly journals The Major Chemical Constituents of Teosinte Grown as Mono and Mixed Cropping with Legumes in different Sowing Date

2021 ◽  
Vol 7 ◽  
pp. 44-53
Author(s):  
Birendra Khanal ◽  
Naba Raj Devkota ◽  
Megh Raj Tiwari ◽  
Neena Amatya Gorkhali
Keyword(s):  
Chemical Constituents ◽  
Sowing Date ◽  
Neutral Detergent Fiber ◽  
Mixed Cropping ◽  
Mean Values ◽  
Average Value ◽  
Sowing Dates ◽  
Main Plot ◽  
Major Chemical

Teosinte (Euchlaena mexicana) is one of the most popular summer growing cereal fodder, yet with comparatively low level of chemical constituents. The quality of this fodder can be improved through better by cultivation management including sowing dates and mixed cropping with legume. The main objective of this study was to determine the forage quality as reflected by major chemical constituents of pure stands of teosinte and binary mixtures of teosinte with commonly available legumes under different dates of sowing. Four fodder combinations; teosinte mono crop, teosinte+ cowpea, tesosinte+ rice bean, and teosinte+ lablab bean was arranged to cultivate in three different date of sowing in the field in a Split Plot Design with 5 replications. Main plot treatments were different sowing dates and sub-plot treatments were combinations of fodder species. Dry herbage mass production, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL) and Ash were determined. The results showed that the significantly the highest Dry herbage and CP were obtained from fodder combination teosinte+ cowpea if sown at 18th April, whereas the significantly highest mean values of ADF and NDF were obtained for teosinte mono fodder crop. However, the lowest average value of ADF and NDF was obtained for fodder combination teosinte with cowpea. The average value of Ash and ADL of both harvest for fodder combination and date of sowing was statistically similar (p>0.05). The effect of treatments interaction/combination on cumulative dry herbage was statistically high (p<0.05) when teosinte+ cowpea was sown at 18th April. However, effect of treatments interaction/combination on average value of CP, NDF, ADF, ADL and Ash of both harvests (g/kg DM) was statistically similar (p>0.05). The results showed that mixture of teosinte with cowpea sown at 18th April could be the best combination in terms of quantity as well as for major chemical constituents that could reflect better quality of fodder harvest.

scholarly journals Effect of sowing dates on different rapeseed varieties under rain fed condition

2021 ◽  
Vol 4 (1) ◽  
pp. 176-190
Author(s):  
Gaurav Ranabhat ◽  
Pramod Tiwari ◽  
Ashmita Dhakal ◽  
Pramod Oli ◽  
Amira Chapagain ◽  
...  
Keyword(s):  
Seed Yield ◽  
Biomass Yield ◽  
Sowing Date ◽  
Oilseed Crop ◽  
Yield Attributes ◽  
Mean Values ◽  
Sowing Dates ◽  
Biological Yield ◽  
Final Yield ◽  
Growth Attributes

Rapeseed is a leading oilseed crop of Nepal occupying 85% of total oilseed cultivation area. This research was conducted to determine the response of different sowing dates on different rapeseed varieties in their final yield under the rain fed condition in Phulbari, Dang. Two rapeseed varieties Unnati and Surkhet Local on three dates of sowing Oct 4, Oct 24 and Nov 14 were tested under two factorial RCBD design in the year 2018 A.D. Data consisted growth attributes like plant height, branch per plant, no. of siliqua per plant, aborted siliqua and siliqua abortion percentage and yield attributes such as biological yield, biomass yield, seed yield, harvest index and test weight. Statistically no difference was found between varieties whereas differences were found on different sowing dates. Result showed that among the varieties, the highest yield (8.59 q/ha) was obtained in Surkhet Local than in Unnati (8.54 q/ha). In case of sowing dates, higher seed yield was obtained in Oct 4 sown crop (15.93 q/ha) followed by Oct 24 (7.47 q/ha) and Nov 14 (2.29 q/ha).The higher seed yield obtained in early sowing is due to shorter vegetative and longer reproductive phase. The comparison of mean values of the seed yield for interaction between variety and sowing date showed that variety Surkhet Local sown in Oct 4 plant had the highest seed yield (16.33 q/ha) followed by variety Unnati on same sowing date (15.54 q/ha). Based on the result obtained, Surkhet Local*Oct 4 performed better in Dang condition.

scholarly journals Effects of Sowing Date and Fungicide on Seedling Establishment of Pearl Millet Genotypes Infected with Downy Mildew Disease

2021 ◽  
Vol 3 (1) ◽  
pp. 44-50
Author(s):  
Sheriff H. H. ◽  
Gurama A. U. ◽  
Aliyu M. ◽  
Ahmed A.
Keyword(s):  
Downy Mildew ◽  
Pearl Millet ◽  
Seedling Establishment ◽  
Block Design ◽  
Sowing Date ◽  
Limiting Factor ◽  
Mean Values ◽  
Sowing Dates ◽  
Better Than ◽  
Downy Mildew Disease

Downy mildew caused by Sclerospora graminicola (Sacc.) Schroet is a major limiting factor to the production of pearl millet globally. Therefore, a field trial was carried out during the 2018 and 2019 rainy seasons at Bauchi and Maiduguri located in the Northern Guinea and Sudan Savannah of Nigeria, respectively. The aim was to evaluate the effects of different sowing dates and a fungicide on seedlings establishment of three pearl millet genotypes infected with downy mildew disease. Randomized Complete Block Design was used with a factorial arrangement of treatments, which comprised three pearl millet genotypes (Gero, Maiwa, Dauro), three sowing dates (late-June, mid-July and late-July) and metalaxyl fungicide (treated and untreated). Results for genotypes consistently showed that Maiwa performed better than Gero and Dauro. In terms of the sowing date, the performance of millet was better in the first sowing date (late-June), followed by the second date (mid-July) and then the third date (late-July). Mean values of the seedling establishment were significantly decreased with delay in sowing date. Results, in respect of the fungicide treatments, generally indicated a higher seedling stands in the treated (78.6 - 87.4%) than untreated seed (70.9 - 81.1%) across the locations. These findings revealed that treated seeds with metalaxyl fungicide and early sowing give better seedling establishment in pearl millet.

scholarly journals Sowing dates and densities on physiological potential of seeds of white oat cultivars

2020 ◽  
Vol 42 ◽  
Author(s):  
José Henrique Bizzarri Bazzo ◽  
Klever Márcio Antunes Arruda ◽  
Inês Cristina de Batista Fonseca ◽  
Claudemir Zucareli
Keyword(s):  
Polynomial Regression ◽  
Seedling Emergence ◽  
Sowing Date ◽  
Germination Percentage ◽  
Joint Analysis ◽  
Mean Values ◽  
Growing Period ◽  
Seedling Length ◽  
Sowing Dates ◽  
Oat Cultivars

Abstract: The aim of this study was to evaluate the physiological potential of seeds of white oat cultivars grown at different sowing dates and densities. Two independent experiments were conducted with two different sowing dates in a randomized block experimental design in a 4 × 2 factorial arrangement, with four replications. The treatments consisted of four sowing densities (180, 240, 300, and 360 viable seed.m-2) and two cultivars (IPR Afrodite and IPR Artemis). The following evaluations were made: thousand seed weight, germination percentage, first germination count, seedling length, seedling dry matter, emergence speed index, and seedling emergence in sand. Joint analysis of variance was carried out on the data regarding sowing dates separately for the cultivars. The mean values for sowing dates were compared by the F test; and polynomial regression analysis up to the second degree at 5% probability was conducted on the densities. The seeds produced by the plants grown from the first sowing date had better vigor than those produced by plants from the later sowing date. The increase in sowing density reduces the weight and vigor of the seeds produced by plants from the second sowing date. For the IPR Afrodite and IPR Artemis cultivars, the use of 180 seed.m-2 in the first growing period allows production of seeds with greater physiological potential.

scholarly journals Agronomic characteristics and macronutrient export of grain sorghum hybrids from different sowing dates

2017 ◽  
Vol 41 (1) ◽  
pp. 7-14 ◽  
Author(s):  
César Henrique Souza Zandonadi ◽  
Carlos Juliano Brant Albuquerque ◽  
Rogério Soares de Freitas ◽  
Alyne Dantas Mendes de Paula ◽  
Marina Alves Clemente
Keyword(s):  
Block Design ◽  
Production Capacity ◽  
Sowing Date ◽  
Grain Sorghum ◽  
Absorption Capacity ◽  
Mean Values ◽  
Agronomic Characteristics ◽  
Brazilian Savannah ◽  
Sowing Dates ◽  
Sorghum Grains

ABSTRACT Brazilian off-season cropping is increasing the production of cereals, particularly in the Brazilian savannah. Sorghum has been widely used for its grain production capacity and dry matter. Several hybrids are commercially available, each with its own peculiar nutrient absorption capacity. Thus, this study analyzed the agronomic characteristics and nutrient exportation in grain sorghum hybrids sown on different dates. The experiment was conducted at the Paulista Agency Regional Center of Agricultural Technology (APTA) in the city of Votuporanga, São Paulo. The experiment was conducted in a randomized block design with four replications and 4 hybrids. Sorghum hybrids (50A10, 50A50, BUSTER and 1G282) were the different treatments sown on four different dates, beginning with February 26, 2013, with the other dates 17, 30 and 41 days after the first sowing (DAFS). Each sowing date was considered an individual experiment and, subsequently, grouped for analysis to compare characteristics. Macronutrient content in the grain, one thousand grain weight, productivity and exportation of macronutrients (kg ha-1) by grains in the area were evaluated. The productivity of the sorghum hybrids varied depending on the sowing dates. The one thousand grain mass of the sorghum hybrids varied depending on the sowing dates. The average exportation of macronutrients by sorghum grains is as follows, in decreasing order: N> K> P>Ca> Mg> S. The mean values of macronutrient accumulation needed to produce one ton of sorghum grains are as follows: 20.05 kg N, 3.33 kg P, 3.70 kg K, 3.49 kg Ca, 1.77 kg Mg, and 0.72 kg S.

scholarly journals Effect of Sowing Dates, Phosphorous and Potassium Fertilizer Rates on Phenological, Growth and Yield Aspects of Okra (Abelmoschus esculentus L) in Hamelmalo Subzone, Eritrea

2021 ◽  
pp. 93-102
Author(s):  
Bahran Kinfe ◽  
G. Sethumadhava Rao
Keyword(s):  
Block Design ◽  
Total Yield ◽  
Late Summer ◽  
Sowing Date ◽  
Fruit Weight ◽  
Abelmoschus Esculentus ◽  
Growth And Yield ◽  
Potassium Fertilizer ◽  
Mean Values ◽  
Sowing Dates

The field experiment was conducted, in the fields of Hamelmalo Agricultural College, to evaluate the response of sowing-dates and PK (Phosphorous and Potassium) fertilizer levels on phenological aspects, yield and yield components of okra (Abelmoschus esculentus L). The experiment was done through a factorial randomized complete block design (RCBD) where each treatment was replicated three times. The two factors were: sowing-dates which was composed of three sowing dates; namely, middle kiremti (end of July i.e., mid-summer), late kiremti (middle of August- late-summer) and early qewee (early September-early autumn) and P: K fertilizers which was composed of five rates (0kg/ha, 125 kg/ha (75:50), 150 kg/ha (90:60), 175 kg/ha (105:70) and 200 kg/ha (120:80). Results showed that, the highest significant mean values of leaf area (389.4cm2), leaf numbers (28.2) were recorded from middle kiremti sowing date coupled with 320kg/ha and 175kg/ha PK rates respectively. Besides this the highest significant values of both number of fruits (43.8) and total yield (15.26t/ha) were obtained from highest PK rate coupled with late kiremti and middle kiremti respectively.  The sole effects of the PK rates as well as the sowing dates were found to be significant on all the parameters mentioned above including individual fruit weight.  It is therefore the sowing during late kiremti coupled with application of 200kg/ha kg/ha was the best for getting the best economic returns.

EFFECT OF SOWING DATE ON GRAIN YIELD OF CRAB GRASS

2001 ◽  
Vol 49 (3) ◽  
pp. 293-297
Author(s):  
S. O. Bakare ◽  
M. G. M. Kolo ◽  
J. A. Oladiran
Keyword(s):  
Grain Yield ◽  
Interaction Effect ◽  
Significant Interaction ◽  
Sowing Date ◽  
Yield Data ◽  
Significant Interaction Effect ◽  
Sowing Dates

There was a significant interaction effect between the variety and the sowing date for the number of productive tillers, indicating that the response to sowing date varied with the variety. A significant reduction in the number of productive tillers became evident when sowing was delayed till 26 June in the straggling variety as compared to sowing dates in May. Lower numbers of productive tillers were also recorded when the sowing of the erect variety was further delayed till 10 July. The grain yield data showed that it is not advisable to sow the straggling variety later than 12 June, while sowing may continue till about 26 June for the erect variety in the study area.

Application of physiological understanding in soybean improvement. I. Understanding phenological constraints to adaptation and yield potential

2011 ◽  
Vol 62 (1) ◽  
pp. 1 ◽  
Author(s):  
R. J. Lawn ◽  
A. T. James
Keyword(s):  
Seed Yield ◽  
Environmental Control ◽  
Thermal Environment ◽  
Sowing Date ◽  
Companion Paper ◽  
Interaction Effects ◽  
Yield Potential ◽  
Environment Interaction ◽  
Sowing Dates ◽  
Eastern Australia

The purpose of this paper and its companion1 is to describe how, in eastern Australia, soybean improvement, in terms of both breeding and agronomy, has been informed and influenced over the past four decades by physiological understanding of the environmental control of phenology. This first paper describes how initial attempts to grow soybean in eastern Australia, using varieties and production practices from the southern USA, met with limited success due to large variety × environment interaction effects on seed yield. In particular, there were large variety × location, variety × sowing date, and variety × sowing date × density effects. These various interaction effects were ultimately explained in terms of the effects of photo-thermal environment on the phenology of different varieties, and the consequences for radiation interception, dry matter production, harvest index, and seed yield. This knowledge enabled the formulation of agronomic practices to optimise sowing date and planting arrangement to suit particular varieties, and underpinned the establishment of commercial production in south-eastern Queensland in the early 1970s. It also influenced the establishment and operation over the next three decades of several separate breeding programs, each targeting phenological adaptation to specific latitudinal regions of eastern Australia. This paper also describes how physiological developments internationally, particularly the discovery of the long juvenile trait and to a lesser extent the semi-dwarf ideotype, subsequently enabled an approach to be conceived for broadening the phenological adaptation of soybeans across latitudes and sowing dates. The application of this approach, and its outcomes in terms of varietal improvement, agronomic management, and the structure of the breeding program, are described in the companion paper.

scholarly journals Effective Seed Yield and Flowering Synchrony of Parents of CIMMYT Three-Way-Cross Tropical Maize Hybrids

Agriculture ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 161
Author(s):  
Alberto A. Chassaigne-Ricciulli ◽  
Leopoldo E. Mendoza-Onofre ◽  
Leobigildo Córdova-Téllez ◽  
Aquiles Carballo-Carballo ◽  
Félix M. San Vicente-García ◽  
...  
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Grain Filling ◽  
Sowing Date ◽  
Planting Density ◽  
Planting Dates ◽  
Flowering Synchrony ◽  
Sowing Dates ◽  
Grain Filling Period ◽  
Hybrid Maize

Genotype, environmental temperature, and agronomic management of parents influence seed yield in three-way cross hybrid maize seed production. The objective of this research was to generate information on the seed production of six three-way cross hybrids and their progenitors, adapted to tropical lowlands. Data on days to—and duration of—flowering, distance to spike and stigmas, and seed yield of five female single crosses and five male inbred lines were recorded for different combinations of four planting densities and four sowing dates in Mexico. The effect of planting density was not significant. The male inbred line T10 was the earliest and highest seed yield and T31 the latest, occupying second place in yield. The single crosses T32/T10 and T13/T14 were the earliest and had the highest effective seed yield. At the earliest sowing date, the females were later in their flowering, accumulated fewer growing degree days (GDD), and obtained higher yields since the grain-filling period coincided with hot days and cool nights. To achieve greater floral synchronization and therefore greater production of hybrid seed, differential planting dates for parents are recommended based on information from the accumulated GDD of each parent. The three-way cross hybrids were classified according to the expected seed yield of the females and the complexity in the synchronization of flowering of their parents.

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