or fruit production as a consequence of the lack of optimum pollination conditions (CLARK and FRYER, 1920; ARMSTRONG and WHITE, 1935; VALLEAU, 1918; KVAALE, 1927; and many others). In order to mini mize the influence of poor pollen producers, systematic planning of a field planting or an orchard might be necessary. Above all, the im portant reason for its wide popularity is its potential use in the com mercial production of hybrid seed. A male-sterile plant is an effective female for a crossing program and its employment renders the labori ous procedure of emasculation superfluous. ]ONES and EMSWELLER (1937) and STEPHENS (1937) were probably the first to outline a scheme of its application in onion and sorghum respectively. However certain specific problems have limited the practicability and hence some of them will be mentioned in a later seetion (Section VIII). Lately several attempts have been made to obtain some chemie al method for the artificial induction of male sterility. However, for a successful approach to the induction problem a thorough understan ding of various pathways that bring about pollen abortion in naturally occurring cases, would be of great value. It may be hoped that data from these induction experiments alongwith the available biochemi cal analyses would lead to the emergence and elucidation of useful information of both theoretical and practical interest.

" . . . . . . Nature has something more in view than that its own proper males should fecundate each blossom. " Andrew Knight Philosophical Transactions, 1799 Sterility implicating the male sex solely presents a paradoxical situation in which universality and uniqueness are harmoniously blended. It maintains a built-in outbreeding system but is not an isolating mechanism, as male steriles, the "self-emasculated" plants, outcross with their male fertile sibs normally. Both genes (nuclear and cytoplasmic) and environment, individually as well as conjointly, induce male sterility, the former being genetic and the latter nongenetic. Genetic male sterility is controlled either exclusively by nuclear genes (ms) or by the complementary action of nuclear (lr) and cytoplasmic (c) genes. The former is termed genic and the latter gene-cytoplasmic male sterility. Whereas genic male sterility exhibits Mendelian inheritance, gene-cytoplasmic male sterility is non-Mendelian, with specific transmissibility of the maternal cytoplasm type. Genetic male sterility is documented in 617 species and species crosses com prising 320 species, 162 genera and 43 families. Of these, genic male sterility occurs in 216 species and 17 species crosses and gene-cytoplasmic male sterility in 16 species and 271 species crosses. The Predominance of species exhibiting genic male sterility and of species crosses exhibiting gene-cytoplasmic male sterility is due to the fact that for the male sterility expression in the former, mutation of nuclear genes is required, but in the latter, mutations of both nuclear and cytoplasmic genes are necessary.

Provides an invaluable reference and source book on plant embryogenesis for cell and molecular biologists, and plant biotechnologists.

The book discusses how to improve crop species and varieties through different breeding methods. It covers history, origin of crop species, reproduction in crop species, self incompatibility, male sterility, selection in crop plants, improvement of crop species and intellectual property right. This book cover the syllabus of fundamentals of plant breeding for UG course approved by ICAR.

"Frontiers on Recent Developments in Plant Science is an edited, peer-reviewed volume comprised of a collection of individual chapters from leading research groups across different continents. Due to its multidisciplinary nature, the combined experiences a"

Plant reproductive biology has undergone a revolution during the past five years, with the cloning, sequencing and localization of the genes important in reproduction. These advantages in plant molecular biology have led to exciting applications in plant biotechnology, including the genetic engineering of male sterility and other reproductive processes. This book presents an interesting and contemporary account of these new developments from the scientists in whose laboratories they have been made. The chapters focus on two areas: the molecular biology of self-incompatibility, which is the system of self-recognition controlled by the S-gene and related genes; and the cellular and molecular biology of pollen development and genetic dissection of male sterility. Some chapters feature Arabidopsis, with its unique genetic system. Reproduction is vital for seed production in crop plants, and this book presents new approaches to manipulate plant breeding systems for the 21st century.

Heterosis and Hybrid Seed Production in Agronomic Crops discusses how heterosis or “hybrid vigor” has played a major role in improving crop productivity and quality in order to feed the ever-increasing human population, particularly in developing countries. Plant breeders, agronomists, seed producers, and farmers will discover why the development of hybrids in the world's major food crops and why the methods of hybrid seed production are critical for achieving this goal. This landmark book deals with heterosis and hybrid seed production of major agronomic crops such as wheat, rice, maize, sorghum, cotton, sunflower, and rapeseed. Through Heterosis and Hybrid Seed Production in Agronomic Crops, you will discover valuable information on hybrid seed production methods that is not available in any other single volume. This unique book contains relevant and essential information about important procedures to help increase crop yield, including: methods for deriving second cycle inbred lines for hybrid maize possibilities for hybrid seed production in wheat techniques of hybrid sorghum seed production production of hybrid seeds using male sterile lines of cotton agronomic management in seed production plots of sunflower seed production technology of hybrid rapeseed advances in hybrid seed production technology of rice in China Heterosis and Hybrid Seed Production in Agronomic Crops gives you a global perspective on essential food crops in all parts of the world. This informative guide will help you use hybrid seed production methods with important agricultural crops and increase the quality of these vital and essential food sources.

The study of plant development using molecular and genetic techniques is rapidly becoming one of the most active areas of research on flowering plants. Developmental Biology of Flowering Plants relates classical developmental work with the outstanding problems of the future in the study of plant development. An important feature of this book is the integration of results from molecular and genetic studies on various aspects of plant development in a cellular and physiological context.

Written by the leading experts in the field, this book examines the evolutionary advantages of gender dimorphism and sexual dimorphism in flowering plants. Divided into three sections: the first introduces readers to the tremendous variety of breeding systems and their evolution in plants and sets the stage for a consideration of the evolution of dimorphism in reproductive and non-reproductive characters. The second section deals with the evolution of secondary sexual characters, including the theory related to the evolution of sexual dimorphism and its empirical patterns, while the last section deals with the genetics of gender expression and of secondary sexual characters.