Cytoplasmic-genetic Male Sterile Lines Research Articles

Pant CMS3A Unique improved cytoplasmic genetic male sterile line with exerted panicles for potential hybrid seed production in rice

Pant CMS3A Unique improved cytoplasmic genetic male sterile line with exerted panicles for potential hybrid seed production in rice

USE OF MALE STERILITY AND SYNTHESIS OF MAINTAINER LINE FOR HYBRID SEED PRODUCTION IN ONION (Allium cepa L.)

Field experiment was carried out and one cytoplasmic genetic male sterile line (Smsms) and two local lines were identified as maintainer lines (Fmsms). These two crossed materials namely 3(Shallot*Local) and 4 (Shallot *Local) produced 100 per cent male sterile progeny in full sib and backcross generations. The Shallot * market cultivar produced both male fertile and male sterile segregating progenies. It indicated that the market material is probably determined by dominant and recessive independently acting genes which genetically impure lines. All other crossed materials produced 100 per cent male fertile progeny upon crossing with shallot. So, in backcross generations, the male sterile plants were more when local was used as recurrent parent. Thus, the local cultivar can be used as maintainer line for “Shallot”. The performance of 904 F1 and 905 F1 hybrids over check and better parent was found to be preferably better using CMS system. So, considering the genetics and stability of the male sterility mechanism, further studies are needed towards hybrid variety development in Bangladesh.

Identification of superior parents and hybrids for improving pigeonpea [Cajanus cajan (L.) Millsp.] yield

A study involving three cytoplasmic-genetic male sterile lines and 14 diverse pollinators were crossed in a line × tester design during Kharif 2011. The resultant 42 hybrids and their parents were evaluated in a lattice design. Analysis of variance revealed that the ratio of variance due to GCA to SCA was less than unity for all the traits except secondary branches indicating that these traits may be under the influence of non additive gene action and these characters are more likely to be improved through heterosis breeding. The gca effects of parents revealed that ICPA-2043, ICPA-2047, GRG-2009-4 and ICPL-20 were good general combiners for seed yield and it’s direct components. The top three crosses exhibiting high specific combing ability effects along with their Per se performance, standard heterosis and gca status of the parents indicated that the cross combination ICPA-2047 x GRG-2009-4 was good specific combiner for seed yield per plant, number of secondary branches and number of pods per plant.

Heterosis and combining ability for earliness, plant growth, yield and fruit attributes in hot pepper (Capsicum annuum L.) involving genetic and cytoplasmic-genetic male sterile lines

Twelve genetically diverse inbred lines, including a cytoplasmic-genetic male sterile (CGMS) and a genetic male sterile (GMS) line, of hot pepper (Capsicum annuum L.) were crossed in half-diallel to produce 66 F1 hybrids. The seeds of 78 genotypes were evaluated for 11 characters in a randomized complete block design (RCBD) with three replications for 2 years, viz., 2008–2009 and 2009–2010 at Punjab Agricultural University, Ludhiana, India. The pooled analysis showed that both additive and non-additive genetic variances were important in controlling the expression of all the traits, however additive variance for days to flowering, fruit length, fruit width, average fruit weight, and pericarp thickness, and non-additive variance for total fruit yield plant−1 and plant spread were comparatively more important. The GMS line MS 341 was a good general combiner for four parameters, viz., early yield, number of fruits plant−1, fruit length and number of seeds fruit−1. The CGMS line CC 141 was a good general combiner for three characters, viz., fruit length, plant height and plant spread. The inbred line SL 461 was the best general combiner for fruit length and total fruit yield plant−1, DL 161 for days to flowering and number of fruits plant−1, SD 463 for average fruit weight and pericarp thickness, PP 402 for early yield and fruit width. The combining ability of the parental lines had a nice consonance with their per se performance. Most of the F1 hybrids have higher early and total yield, along with higher number of fruits, fruit length, plant height and plant spread, but lower pericarp thickness and fruit width. The magnitude of heterobeltiosis varied from −35.77 to 5.00% for days to flowering, −64.94 to 238.48% for early yield, −79.30 to 205.95% for number of fruits plant−1, −4.72 to 39.64% for fruit length, −20.60 to 10.41% for fruit width, −28.65 to 57.52% for average fruit weight, −37.98 to 14.39 for pericarp thickness, −80.70 to 89.94% for number of seeds fruit−1, −1.80 to 32.21% for plant height, −13.77 to 20.66% for plant spread, and −71.82 to 331.11% for total fruit yield plant−1. The study offers the opportunity of transferring male sterility in to good combiner lines, viz., SD 463, SL 461, US 501, PP 402 and DL 161, and evaluating the top 10 hybrids, exhibiting more than 100% heterobeltiosis for total fruit yield plant−1 along with high specific combining ability and per se performance, over multi-locations to test their stability.

Environmental Impact on the Combining Ability of Fiber Traits and Seed-Cotton Yield in Cotton

Hybrids are widely accepted in all crops to improve yield, but genotype × environment interaction plays an important role in achieving high yield and superior quality traits. Three cytoplasmic genetic male sterile lines and seven testers of Gossypium hirsutum L. varying in seed cotton yield and fiber traits were assessed for hybrid vigor using a line × tester system across three different locations. The objectives of this study were to estimate 1) level of heterosis and specific combining ability (SCA) for fiber traits and seed‐cotton yield; 2) correlation between general combining ability (GCA) and line per se, as well as correlation between genetic distance and SCA; and 3) influence of environmental factors on combining ability estimates and trait correlations in parents and hybrids. The level of heterosis was acceptable for seed-cotton yield (32.46%) and fiber traits except uniformity ratio and fiber elongation. Combining-ability analysis across environments showed significant (P < 0.01) effects for genotypes, GCA, SCA, genotype × environment, GCA × environment, and SCA × environment interactions. Combining-ability variance revealed predominance of non-additive gene effects for seed-cotton yield, gin turnout, and micronaire, and additive gene effects for bundle strength and fiber elongation. A positive relationship was found between GCA effects and mean performance of parents, midparent value, and hybrid performance, with emphasis on the dominant gene effect for most of the traits studied. Positive correlation was found between GD and SCA effect. Environmental factors significantly affected the expression of fiber traits and seed‐cotton yield. The correlations among fiber traits and seed-cotton yield emphasized the possibility for improving both yield and fiber properties.

Development of new cytoplasmic-genetic male-sterile lines in pigeonpea from crosses betweenCajanus cajan (L. Millsp. andC. scarabaeoides (L.) Thouars

Exploitation of hybrid vigour is quite possible in cross-pollinated crops. However, pigeonpea is a grain legume crop with a moderate level of cross-pollination (20-70%), which is mainly aided by insect pollinators. As a first step, hybrids based on genetic male sterility (GMS) were developed in pigeonpea, but the hybrid seed production technique is not farmer-friendly, because in the hybrid seed production plot 50% of the population, which are male-fertile in the female rows, have to be eliminated in time before contamination. This requires skilled labour and is a time-consuming process, which increases the cost of hybrid seed production. Therefore, the objective of this study was to develop cytoplasmic-genetic male-sterile (CGMS) lines in pigeonpea through wide hybridization, which would be very suitable for hybrid seed production. Two CGMS lines, viz. CORG 990052 A and CORG 990047, were developed by interspecific hybridization of Cajanus cajan and C. scarabaeoides. Restorers were identified and three CGMS-based pigeonpea hybrids were developed. The hybrid COPH 3 is found to be promising in Tamil Nadu State, India.

Expression of resistance in rice hybrids to Pyricularia grisea

Thirty-nine rice (Oryza sativa) hybrids and their restorers were assessed for vertical resistance to Pyricularia grisea in the rice blast nursery, and in artificial inoculation tests with two pathotypes, under controlled greenhouse conditions. The hybrids were developed from cytoplasmic genetic male sterile lines 046I and IR 58025A, derived from WA cytoplasm. In the rice blast nursery all hybrids showed susceptible reaction varying from 5 to 9. Compatible and incompatible leaf blast reactions of hybrids to two pathotypes, IC-1 and IB-45, were observed in inoculation tests. A majority of the hybrids were resistant when the restorer was resistant. However, seven of the 25 F1 hybrids exhibited susceptible reactions even when one of the parents was resistant to a pathotype. The partial resistance of 11 hybrids and their parents that showed compatible reactions to two pathotypes was analyzed. Differential interaction between isolates and genotypes was observed for partial resistance in relation to both disease severity and lesion number indicating the specific nature of partial resistance.

Breeding of widely compatible restorer lines in rice (Oryza sativa L.) through anther culture

Following anther culture of various F1 hybrids of indica restorer (R) lines/wide compatible varieties (WCVs) and japonica R lines/WCVs, the homozygous diploid plants (2n) generated were test-crossed with indica WA type cytoplasmic-genetic male sterile (CMS) line Zhanshan 97A (WA), indica testers Nanjing 11 and Nante, japonica BT CMS line Hanfeng A (BT), and japonica testers Balilla and Akihikari to identify widely compatible restorer lines. The results of this study showed that among the diploid pollen plants generated from F1 hybrids of indica R lines/WCVs, 36.7% and 64.7% possessed normal fertility restoration ability (rate of seed-setting > 80%) to Hanfeng A and Zhanshan 97A, respectively. 71.3% and 32.3% had normal fertility restoration ability to Hanfeng A and Zhanshan 97A, respectively, in diploid pollen plants derived from the japonica R lines/WCVs F1's anther culture. Several widely compatible R lines were selected from anther culture of F1 hybrids of indica R lines/WCVs and japonica R lines/WCVs. These widely compatible R lines derived from diploid pollen plants showed good wide compatibility and restoration ability both to WA and BT type CMS lines. Strong standard heterosis of major agronomic traits and yield traits was observed in F1 test-crosses of widely compatible R lines with Hanfeng A and Zhanshan 97A. The wide compatibility in widely compatible R lines H17, H158 and H281 was studied by a set of three-way crosses. Segregation of the fertile plants with seed-setting rate > 70% and semi-fertile plants with seed-setting rate > 69.9% agreed with a ratio of 1:1, indicating that wide compatibility in these widely compatible R lines is governed by a pair of major genes.

Identification of male sterility maintainer lines for Ogura radish (Raphanus sativus L.)

‘Ogura radish’, a cytoplasmic genetic male sterile line, was crossed with four local and three Japanese cultivars to identify maintainer lines. Out of seven F1 families, one cross involving a local cultivar, Aushi, produced 100% male sterile (MS) progeny. The crosses involving the other two local cultivars, Tangail Local and Kuni, produced about 90% MS progeny, indicating the presence of maintainer gene(s) for male sterility. The fourth local cultivar, Tasaki, produced 100% male fertile (MF) progeny. All three exotic cultivars appeared to possess the chromosomal gene(s) for controlling the male sterility. In BC1, BC2 and BC3 generations, segregation of MS plants were more frequent when ‘Aushi’ was used as recurrent parent. The expression of male sterility was not affected by seasonal influences. Thus the local cultivar ‘Aushi’ may be used as maintainer line for ‘Ogura radish’. To produce hybrid seed, ‘Tasaki’ can be used as pollinator line as it exhibit high heterosis with ‘Aushi’.

HETEROSIS IN HYBRID RICE

Thiry six hybrids were developed utilising three cytoplasmic genetic male sterile lines (V 20 A, IR 58055 A and IR 62829 A) and twelve testers and they were studied for the extent of heterosis on six quantitative characters viz., days to flowering, panicles per plant, grains per panicle, spikelet fertility. 100- grain weight and grain yield per plant. The hybrid IR 62829 A x CO 37 revealed heterotic vigour for panicles per plant and grain yield per plant.

Cytoplasmically controlled cold tolerance in a cytoplasmic-genetic male sterile line of rice

The cytoplasmic-genetic male sterile line, ‘Krishna-A’ with ‘Kalinga-I’ cytoplasm was developed in rice through repeated backcrossing the completely pollen sterile F1 of the cross ‘Kalinga-I/Krishna’ with the recurrent male parent cv. Krishna. The germination percentage and root-shoot length in ‘Krishna-A’ at 12°C and 9°C indicated a higher degree of tolerance to low temperature than the cold tolerant female parent ‘Kalinga-I’. The high yielding cold tolerant variety ‘Kalinga-I’ was developed from a cross involving the cold tolerant variety ‘Dunghansali’ and the high yielding variety ‘IR 8’. It is inferred that tolerance to low temperature during germination in ‘Krishna-A’ was inherited from the cytoplasm of cv. Dunghansali through ‘Kalinga-I’ besides male sterility. The cytoplasmic control of cold tolerance is reported here for the first time in rice literature. The male sterile line ‘Krishna-A’ because of its tolerance to low temperature would be suitable for the development of hybrid rice especially for areas where low temperature is a problem during germination.

Development of new cytoplasmic genetic male sterile lines through Indica × Japonica hybridization in rice

From 28 Indica-Japonica crosses, two Indica cultivars, V.20B and Sattari were identified to possess male sterile cytoplasm with fertility restoring genes. It was possible to develop a new Japonica cytoplasmic genetic male sterile line (Zhunghua-1) on Indica male sterile cytoplasm (V 20B) by repeated backcrossing the complete pollen sterile plants of V 20B x Zhunghua-1 to the recurring male parent, Zhunghua-1. The study indicated that it would be possible to develop male sterile lines rom indica-japonica crosses only when there is sufficient amount of reciprocal differences with respect to pollen sterility. Further, it was inferred that it would be easier to develop Japonica male sterile lines on Indica cytoplasm than developing Indica male sterile line with japonica cytoplasm.

Heterosis in rice hybrids

One hundred and thirtysix hybrids were developed utilizing four cytoplasmic genetic male sterile lines (V 20A, Zhen Shan 97A, IR 46829A and IR 46830A) and 34 effective restorers. Heterosis, heterobeltiosis and standard heterosis were found to be significant for grain yield and other yield attributing characters in most of the hybrids. The heterosis for grain yield was mainly due to the significant heterosis for the number of spikelets per panicle, test weight and total dry matter accumulation. Interestingly, it was found that most of the higher yielding hybrids were accompanied by significant negative heterosis for harvest index. Hybrids shorter than the shortest parent and earlier than the earliest parent were not observed; hybrids with intermediate to tall plant height having nonlodging habit could be developed. Eighteen hybrids gave more than 20% grain yield than the standard checks. These were evaluated for their stable and consistent yield performance over four seasons. The results on analysis for stability parameters indicated that the hybrids V 20A × Himdhan and Zhen Shan 97A × Mahsuri were stable over environments.

New sources of cytoplasmic-genetic male sterility in cultivated indica rices

Four indica cultivars viz. Kalinga-I, Ptb. 10, IR 27280-13-3-3-3 and Co. 41 were found to possess male sterile cytoplasm with fertility restoring genes while the cultivar Krishna was found to maintain the male sterility in all the cases. All the plants in the F1 of Kalinga-I × Krishna were observed to be completely male sterile and continued to show complete pollen sterility in subsequent backcross generations when backcrossed with recurring pollen parent, Krishna. Thus, it was posible to develop a new cytoplasmic-genetic male sterile line in indica rice (Krishna A) with Kalinga-I male sterile cytoplasm and this male sterile cytoplasm was found to be genetically different from others. Further, the newly developed male sterile line (Krishna A) was observed to be tolerant for low temperature at seedling stage.

Cytoplasmic-genetic male sterility in radish (Raphanus sativus L.). Identification of maintainers, inheritance of male sterility and effect of environmental factors

Research has been carried out on identification of maintainers for cytoplasmic-genetic male sterile lines in Japanese and European radish, on the mode of inheritance of male sterility and on the effect of environmental factors on the expression of this character.

Stability of pollen sterility in cytoplasmic-genetic male sterile lines in rice

On the basis of the shape and staining pattern of pollen grains, 22 cytoplasmicgenetic male sterile lines of 5 different cytosterility systems in rice could be classified into 4 categories, viz., unstained withered sterile, unstained spherical sterile, stained round sterile and stained round fertile. Using this system, the cytoplasmic-genetic male sterile lines were classified into 5 groups, characterised by relative frequency of the different classes of pollen grains.

Isolation of Fertility Restorers and Maintainers for Cytoplasmic Genetic Male Sterile Line

Isolation of Fertility Restorers and Maintainers for Cytoplasmic Genetic Male Sterile Line

New Maintainers and Restorers for Chinese Cytoplasmic-Genetic Male-Sterile Lines

New Maintainers and Restorers for Chinese Cytoplasmic-Genetic Male-Sterile Lines