In our study, 24 hybrids obtained by diallel cross between ecotypes of okra were subjected to analysis of their combining ability effects and hybrid vigor for. ABSTRACT. High heterosis values can be obtained using hybrid okra seeds. However, despite high heterotic values, it is very difficult to produce hybrid okra. Studies on Heterosis in Okra (Abelmoschus esculentus (L.) Moench) The results revealed that the standard heterosis for fruit yield per plant was maximum in.
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Heterosis in okra hybrids obtained by hybridization of two methods: High heterosis values can be obtained using hybrid okra seeds. However, despite high heterotic values, it is very difficult to produce hybrid okra seeds. The objective of this study was to evaluate an experimental methodology of hybridization.
Two different methods of hybridization were used: These inbred hsterosis were obtained from three selection cycles. Three hybrid types were obtained from the two hybridization methods: The resulting hybrid seeds ni their parents were evaluated via an experiment set up in a randomized block design with four repetitions. At the end of the cycle, morphological characterizations was done of the leaves pubescence, length and width and fruit length, diameter and shape.
Heterosis resulting from the incomplete emasculation followed by natural insect pollination was similar to that heteeosis the traditional hybrid method, being a viable alternative for the production of hybrid okra seeds without losses in heterosis.
Okra Abelmoschus esculentus belongs to the Malvaceae family and originates from Africa.
Studies on Heterosis in Okra (Abelmoschus esculentus (L.) Moench)
The species performs well in tropical regions and is especially well adapted to the tropical regions of Brazil. Santa Cruz 47 is the cultivar most commonly used by Brazilian growers.
Currently, varieties predominate over hybrid seeds in fruit production. Improving productivity is one of the main goals of crop breeding programs. Hybrid seeds are extensively used because they provide one of the fastest ways to increase productivity Paterniani, Current research has also shown the heterotic potential of hybrid okra seeds in targeting greater productivity Mehta et al.
Hybrid seeds are more expensive than varieties; however, hybrid plants are more productive and produce heterosie income Medagam iin al. Despite the superior genetic potential of hybrid okra seeds, seed production remains an obstacle. This dynamic reproductive behavior means that female flowers need to be protected immediately after emasculation to avoid contamination. Some studies show that gametocides can induce male sterility Deepak et al. Nevertheless, gametocides use is still undefined, uncommon, and may be toxic to plants, which results in reduced seed yield.
In fact, there is little research on economical ways of producing hybrid okra seeds. A traditional method is currently used in Brazil for large scale production of hybrid okra seeds.
The heterosus consists of emasculation of the female parent followed by manual crosses, leading to high production costs Nascimento, Higher costs have limited greater exploitation of the heterotic potential of okra hetrrosis and reduced seed availability for growers.
The objective of this study was okfa evaluate an experimental methodology of hybridization for production of hybrid seeds of okra.
International Journal of Biological and Chemical Sciences
The regional climate is humid temperate with hot summers and dry winters. Polystyrene trays cells were filled with a commercial coconut fiber substrate and used to produce seedlings for each line.
The seedlings were planted in the field 35 days after ookra. The plants were distributed 1: The plants were spaced 1. Both inbred lines started flowering approximately 65 days after transplanting. Hybridization commenced at the peak of flowering for both lines, 92 days after transplanting. This strategy guarantees okra seeds of higher physiological quality than seeds produced from the initial phase Purquerio et al. Apis melifera was the most common insect present during flowering.
During this step, two different hybridization methods were used traditional and new on the two inbred lines. Traditional hybridization method THM consisted of emasculating the female parent flowers to expose the flower stigma before anthesis and eliminate the presence of pollen. Next, pollen from the male parent was moved by hand to the stigma of the previously emasculated female flower.
After pollination, the female flowers were protected with Kraft paper to avoid contamination from insect pollination Nascimento, The heeterosis hybridization method IHM consisted of emasculating the female flowers and then allowing pollination to occur via insects that were naturally present at the experiment site. The number of steps was reduced in this process by eliminating the need to protect ih emasculated female flowers or collect male flowers.
This new method was adopted because of the results obtained by Malerbo-Souza et al. Originated fruits of hybridization were harvested when they reached physiological maturity and then the seeds were extracted separately according to hybridization method THM and IHM. After extraction, the seeds were placed in pre-labeled Kraft paper bags and stored. This experiment was set up in randomized blocks design RBD with four replications and used the following statistical model: The five treatments were sown on November 21, Before transplanting, the soil was plowed and harrowed twice and analyzed and corrected for specific crop requirements.
The characteristics of the soil were: Thirty-eight days after sowing, the seedlings were transplanted to the prepared and corrected soil. Twelve plants were planted per plot and spaced 1 m between plants and 1.
Studies on Heterosis in Okra (Abelmoschus esculentus (L.) Moench) 
Thus, the entire experiment covered m 2. Crop treatments insecticides, fungicides, weeding and irrigation were used as recommended for okra Filgueira, heteroxis The fruits were harvested every three days from February 2, until June 27,totalling 41 harvests.
The following agronomic characteristics were determined: A precision scale four decimal places was used. The branches were counted after the last harvest of the experiment. We used the expression proposed by Fehr to evaluate the heterosis.
Heterosis in okra hybrids obtained by hybridization of two methods: traditional and experimental
Ten plants per plot were evaluated. Data for each of the agronomic characters were submitted to analysis of variance F test.
Monte Carmelo, UFU, Significant differences were not observed for the leaf pubescence, but the leaf length of the UFU-QBD and UFU-QBG parents, which were directly involved in obtaining the hybrids, were significantly different Okfa leaf length Compact okra plants i. Conversely, mean fruit diameter An understanding of the morphological characteristics of parents male and female and the consequent hybrids is useful in plant breeding.
Hybridization can be more confidently confirmed by analyzing a combination of these morphological characteristics from parents and hybrids. With this heteroiss, heterosis in okra can be exploited regardless of the method used to obtain hybrid sees. Significant differences in production per plant PP and number of fruits per plant were observed in the different hybrids regardless of hybridization method THM and IHM Table 2. Production per plant This result also demonstrates the similarity in the heterosis of the hybrids regardless of hybridization method IHM or THM.
Some reports show that the number of fruits per plant is related to the action of other types of gene actions such as epistatic additive x additive that allow transgressive segregation Kulkarni et al. In fact, the hybrids obtained in this study showed superiority to their parents regardless of the hybrid seed production method Table 2.
The number of branches per plant was statistically different between the genotypes evaluated in our study. Similarly, heterotic effects were also found for h of NFP Thus, the traditional and more labor intensive okra seed hybridization method THM can be reliably replaced by the less labor intensive method IHM without any loss in heterosis.
An analysis of C1 hybrids vs parents showed the superiority of the hybrids to the parents in terms of production per plant and number of fruits per plant 4, These advantages have already been shown by others Mehta et al. Not only did the C4, C5 and C6 contrasts show the superiority of these three hybrids, regardless of seed hybridization method, they also demonstrated the heterosis of the hybrids and the use of new method of producing hybrid okra seeds.
Acessado em 23 de janeiro de Chemical induction of male sterility and histological studies in okra Abelmoschus esculentus L.
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Indian Journal Agriculcural Sciences