Population improvement and synthetic cultivar production in forage kale (Brassica oleracea L.)

Experimental results are brought together to demonstrate that forage kale population improvement involving full-sib and selfed families can be done on an annual cycle, followed by production of a synthetic cultivar. Furthermore, this new breeding method compares favourably with the two successful methods used to date, namely triple-cross hybrid cultivars from inbreeding and crossbreeding programmes and open-pollinated cultivars from population improvement programmes. The key findings were that natural vernalization of kale in south east Scotland occurred by mid-December so that plants could be pollinated in a glasshouse with heating and lighting by the end of February and seed harvested by the end of May. The resulting full-sib or selfed families could be assessed in a field transplant trial in the same year, from June to November, thus completing an annual cycle. Self-pollination resulted in shorter plants with lower fresh-weight, dry-matter and digestible organic-matter yields, and undesirably higher contents of S-methylcysteine sulphoxide, the haemolytic anaemia factor, and the goitrogenic thiocyanate ion. As a consequence of digestible organic-matter yield being reduced by as much as 22%, the estimated optimum number of selfed parents in a synthetic cultivar was four to eight. Synthetic cultivars are expected to yield as well as triple-cross hybrids as there was no reduction in yield when the latter were open-pollinated.

Assessing Mating Designs Utilized in Cassava Population Improvement

Cassava breeders are curious about appropriate breeding strategies utilized to generate elite genotypes with desired complimentary traits or genes from parents used in crossing. Use of appropriate mating design is influenced by a good understanding of the flower biology of the putative parent plants, type of pollination, crossing technique, pollen dissemination, the presence of male-sterility system, the purpose of the project (that is either breeding or genetic studies), and the size of population needed. The objective of this book chapter is to assess the current knowledge on mating designs, their applications and limitations in cassava improvement. This book chapter discusses the floral biology, genetic improvement, breeding procedures and mating designs in cassava. The information utilized in this study were obtained from various sources including documentary search of the journals, books and websites of relevant stakeholder organizations. Empirical findings of selected mating designs in cassava and their impacts were discussed. Findings serve as a good guide for selection of appropriate mating arrangement to obtain useful information on parents and progenies. Findings are relevant to scientists, researchers, scholars, lecturers and other relevant stakeholders.

Heterosis and Hybrid Crop Breeding: A Multidisciplinary Review

Although hybrid crop varieties are among the most popular agricultural innovations, the rationale for hybrid crop breeding is sometimes misunderstood. Hybrid breeding is slower and more resource-intensive than inbred breeding, but it allows systematic improvement of a population by recurrent selection and exploitation of heterosis simultaneously. Inbred parental lines can identically reproduce both themselves and their F1progeny indefinitely, whereas outbred lines cannot, so uniform outbred lines must be bred indirectly through their inbred parents to harness heterosis. Heterosis is an expected consequence of whole-genome non-additive effects at the population level over evolutionary time. Understanding heterosis from the perspective of molecular genetic mechanisms alone may be elusive, because heterosis is likely an emergent property of populations. Hybrid breeding is a process of recurrent population improvement to maximize hybrid performance. Hybrid breeding is not maximization of heterosisper se, nor testing random combinations of individuals to find an exceptional hybrid, nor using heterosis in place of population improvement. Though there are methods to harness heterosis other than hybrid breeding, such as use of open-pollinated varieties or clonal propagation, they are not currently suitable for all crops or production environments. The use of genomic selection can decrease cycle time and costs in hybrid breeding, particularly by rapidly establishing heterotic pools, reducing testcrossing, and limiting the loss of genetic variance. Open questions in optimal use of genomic selection in hybrid crop breeding programs remain, such as how to choose founders of heterotic pools, the importance of dominance effects in genomic prediction, the necessary frequency of updating the training set with phenotypic information, and how to maintain genetic variance and prevent fixation of deleterious alleles.

MANAGEMENT OF THE ECONOMIC MECHANISM OF PRODUCTION OF ECOLOGICALLY SAFE PRODUCTS

The article presents the theoretical aspects of formation of the economic mechanism of management of production of ecologically safe products. On the basis of the systematic approach identifies key elements in its structure. The authors defined the main principles of formation of the mechanism of production of ecologically safe products. In conditional in modern conditions of uncertainty importance must be a cause, not a consequence. This applies not only to people but also to businesses. Restoring the lost ecological balance and restoration of depleted natural resources require revision of existing approaches to the management of production. The article aims was to study the theoretical aspects of formation of organizational and economic mechanism of production of ecologically safe products and identify key elements in its structure. The mechanism of management is based on the following weekend fundamental elements: principles, objectives, functions and management methods were defined. The system of management includes objectives, functional and system software were established in the article. The building of effective organizational and economic mechanism of management of production of ecologically safe products provides a symbiosis of environmental factors and internal capabilities of subjects of management, which promotes the development of production in the long run were performed. This proposed mechanism would be allow: to solve the food problem in terms of the production of safe and quality products; to restore the lost balance of agro-ecosystems; to strengthen the export potential and reduce the import of high-quality organic products; facilitate the formation of the market of organic products and promote these products among the population; redirect state environmental policy toward the interests of the population, improvement of living conditions, rational use and reproduction of natural resources. The authors specified that the further research would be directed towards the formation mechanism of ecologically efficient use of land for the rational use of agricultural land, conservation and improvement of soil fertility.

Criteria on Sanitary Landfill Suitability Analysis in the Ifugao Province, Philippines

The Philippines is facing an alarming contemporary environment issue on solid wastes generation, which primarily caused by the increase of population, improvement of living standards, rapid economic growth, and industrialization, especially in urban areas. The establishment of a sanitary landfill is highly needed as a mechanism to manage generated solid wastes. However, it requires thorough suitability analysis to foresee and prevent irreversible adverse impacts on society and the ecological environment. This study determined criteria and sub-criterion in the suitability analysis on the establishment of a sanitary landfill in Ifugao Province. This study utilized secondary analysis GIS analysis of required maps based on landfill siting area requirement using ArcMap GIS software licensed to UPLB. Results show that criteria in the suitability analysis classified into economic, environmental, and physical criteria as well as the identified policy consideration, exclusionary zones, and sub-criterion zones. The implementation of suitability analysis through GIS analysis is highly recommended.

Analyzing the genetic relatedness of pigeonpea varieties released over last 58 years in India

The genetic base of 150 pigeonpea varieties released in India during1960 to 2018 was examined. Of these, 89, 57, three, and one variety were developed by pedigree selection, pureline selection, mutation and population improvement, respectively. Examination of pedigree records of 89 pigeonpea varieties developed through pedigree breeding method between 1971 and 2018 traced back to 113 ancestors. The highest mean genetic contribution was recorded for the genotype T 190 (0.051) accompanied by UPAS 120 (0.049) and ICP 8863 (0.043). The ancestor T 190 appeared with highest frequency of 21, directly as one of the parent (male/female) in four varieties and indirectly in the development of 17 varieties. Similarly, the ancestors UPAS 120 and ICP 8863 were more frequently used (in nine varieties) as direct parents followed by T 21 and C 11 (in five varieties). The variety PRG 176 involved the highest number (9) of ancestors during the course of its development followed by the variety VBN (Rg) 3 with eight ancestors. Results indicated that 51.69% (46 of the 89 varieties) of released varieties were developed through bi-parental crossing whereas 48.31% involved multiple parents. The frequent use of a limited number of ancestors has caused the narrow genetic base of released pigeonpea varieties. We recommend large-scale deployment of novel germplasm resources for generating broad-base breeding populations. This will help to obtain improved pigeonpea cultivars with high grain yield, biotic tolerance and climate adaptation.

Genetic study for epistatic gene effects for major yield contributing traits against drought in rice

The study subjected to estimate gene effects and inheritance of quantitative traits of rice with Generation Mean Analysis (GMA). Segregation analysis and estimation of genetic parameters under epistatic model indicated partial dominance and importance of additive effects in the inheritance of drought tolerance, respectively. In present study, absence of epistasis by scaling tests was recorded only for plant height in cross NDR-359 x P0 1564, grains per panicle in cross DSL- 63-8 x NDR- 359, test weight in cross Sarjoo-52 x P0 359, harvest-index in cross NDR-359 x P0 1564 and spikelets per panicle in cross Sarjoo-52 x P0 359 and NDR-359 x P0 1564 in irrigated condition and days to 50 per cent flowering in cross P0 359 x Sonam and harvest-index in cross NDR-359 x P0 1564 in drought condition. In remaining cases, existence of epistasis was observed in either one or both conditions by one or both types of scaling tests. The presence of complementary epistasis in cross P0 359 x Sonam and P0 1564 x Sarjoo-52 would make progress through selection procedures exploiting additive gene actions faster while existence of duplicate epistasis in cross NDR-359 x P0 1564 would have reverse impact. The non-additive gene effects in NDR-359 x P0 1564 for grain yield plant-1may also be utilized for facilitating development of pureline cultivars by involving population improvement methods. Our study concluded that for a large number of traits in six crosses, dominance gene effects and epistatic interactions were significant under drought and irrigated conditions implying that utilization of heterosis through hybrid varieties will act as a budding choice.