Sorghum [Sorghum bicolor (L.) Moench] plays a crucial role as a primary cereal in arid tropical regions, holding global importance for food security and sustainable agriculture. Its cultivation has been steadily increasing in Hungary and various European countries over the past decade. The objective of this investigation was to enhance a Hungarian breeding program at Cereal Research Company, Szeged, by comparing breeding lines from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT-Nairobi) gene bank with those from Hungary. The outcomes of the analysis, which utilized SSR markers to assess 31 genotypes, including 15 from ICRISAT-Nairobi, could potentially contribute to the enhancement of agronomic traits and the development of genetic resistance against various biotic and abiotic stresses. ICRISAT’s extensive collection of accessions, when correlated with Hungarian breeding lines, could guide the selection of diverse parental combinations for segregating progenies. The study classified the genotypes at a 16
Sorghum [Sorghum bicolor (L.) Moench] can benefit from accelerated breeding and release of improved varieties through doubled haploid technology. The technology has been used in speeding up the breeding of other major cereals such as wheat, maize and rice, for which generally widely applied optimised protocols exist. A reproducible protocol for the crop, that can overcome genotype dependency and other species-specific challenges such as phenolic exudation is however lacking. This study aimed at sorghum doubled haploids production thereby contributing to the development of an improved protocol. From the 28 hybrid genotypes, both F-1 registered- and experimental hybrids involved, this study successfully produced haploids from five genotypes and subsequently, four confirmed doubled-haploid lines on W14mf medium or its modification with 1.0 gl(-1) L-proline, 1.0 g(-1) L-asparagine and 1.0 gl(-1) KH2PO4. Medium 190-2Cu was used for regeneration and rooting, which occurred successfully, if the calli were transferred on to it less than 7 days after induction, and temperature was maintained at 25 degrees C under light condition. Genotype dependency was not wholly overcome; however, sorghum's high tillering ability and abiotic stress tolerance were observed to contribute to attainment of haploid plantlets. Spontaneous diploids producing seeds at rates of upto 80.5% were obtained, therefore eliminating the need for colchicine duplication.
Development of sorghum hybrids can immensely benefit from an enhanced anther culture protocol since the resultant doubled haploids would accelerate, as in other major cereal crops, the attainment of homozygosity and fixation of alleles. Production of the hybrids that have got high yielding, stress tolerance and other traits of industrial significance in a shorter time as compared to the current trend can hence be realized. This review presents the advances that have been made in the development of such a protocol, with closer attention to androgenic induction components of pre-treatment, culture media composition and conditions as well as ploidy determination and eventual chromosome doubling. From the findings of this review, it is clear that further work is desired to ensure a protocol, that to a large degree, breaks the genotype dependency trend that has been widely cited to impede the usability of the tested protocols.
Many attempts on optimization of sorghum [Sorghum bicolor (L.) Moench] tissue culture induction media have been made, but the culture system remains with some bottlenecks compared to that of other crops. This study aimed at assessing the suitability of various induction media to produce embryogenic callus (yellow and friable) with high induction rates and reduced phenolic exudation. The six culture medium modifications: 3 based on Murashige and Skoog (MS) medium and one each based on Chu N6, Gamborg B5 and 190-2 media respectively were applied in the culture of mature embryos from 10 sorghum genotypes. Although there was a genotype influence on the attainment of a yellow callus, friability of the callus was determined to be dependent on the culture medium and not the genotype. Half strength MS medium with 0.2 mg/l 2,4-D with 2.8 g/l Gelrite (R) as the gelling agent modified with 1.0 g/l KH2PO4, 1.0 g/l L-proline, 1.0 g/l L-asparagine and 0.16 mg/l CuSO4 center dot 5H(2)O (type E) was found to be the most effective resulting in about 60% yellow coloured callus induction with 25% friability. Addition of CuSO4 center dot 5H(2)O, KH2PO4, L-proline and L-asparagine significantly reduced the phenolic production. Half strength MS medium was observed to contribute to quality callus production when compared to full strength MS media modified with the compounds. The half strength MS medium was also observed to suppress phenolic production. Medium 190-2 produced the highest regeneration frequency (40%) among the 3-regeneration media tested. The results provide information on a suitable sorghum callus induction medium necessary for embryogenesis.
Climate change realities such as high-temperature levels are among the causes of drought episodes affecting the productivity and yield stability of crops worldwide. Breeders, therefore, have a daunting challenge to overcome and a large gap to seal in the agricultural sector arising due to drought through the improvement of new tolerant germplasm. It is in this endeavour that the present study, which included nine winter wheat genotypes grown in the greenhouse, was conducted to evaluate their performance under well-watered and drought stress treatments for the traits: heading time, plant height, above-ground biomass, seed number/plant, grain yield/plant, harvest index, root length and root dry mass. A lower grain yield/plant was observed for each studied genotype under drought stress conditions than for those under well-watered conditions. Additionally, grain yield/plant depression varied from 69.64 to 81.73% depending on the genotype. Positive significant correlations between grain yield/plant and heading time, above-ground biomass, and seed number/plant under the drought stress treatment were obtained. Genotypes that recorded high root dry mass had both high above-ground biomass and seed number/plant under drought stress conditions. Positive correlations between grain yield/plant depression and plant height, seed number/plant, and harvest index depressions were also observed. Grain yield for each genotype under drought stress conditions was recorded, and the varieties 'Plainsman V.', 'GK Bereny' and germplasm 'PC61', 'PC110' showed the best drought tolerance. These genotypes and germplasm will be used in different drought tolerance experiments and breeding programmes.
We investigated the anther culture (AC) efficiency of thirteen F4 combinations of winter wheat (Triticum aestivum L.). The genotype dependency was assessed during the induction of the androgenic entities, i.e. embryo-like structures (ELS), regenerated-, green-, albino-, and transplanted plantlets. The number of green plantlets per 100 anthers (GP/100A) varied from 0.36 to 24.74 GP/100A with a mean of 8.31 GP/100A. Albino plantlets (AP) occurred in each combination, ranging from 0.20 to 22.80 AP/100A with an average value of 5.59 AP/100A. Between 25-87.76 doubled haploid (DH) plants per 100 acclimatised plantlets (DH/100ADP), depending on the combination, with a mean of 59.74% were recovered. We have found the highest DH production in the combinations Béres/Midas, Kalász/Tacitus, Béres/Pamier, and Premio/5009. This improves remarkably the choice of basic genetic material in subsequent crossing programmes. These observations emphasise the usability and efficiency of in vitro AC in producing a large number of DH lines for breeding and the applied researches of winter wheat. Although albinism was found in each combination, it was mitigated by the in vitro AC application.