The genetic basis of male and female sterility in hybrids of Drosophila pseudoobscura-Drosophila persimilis was studied using backcross analysis. Previous studies indirectly assessed male fertility by measuring testis size; these studies concluded that male sterility results from an X chromosome-autosome imbalance. By directly scoring for the production of motile sperm, male sterility is shown ...

F1 hybrid sterility and "hybrid breakdown" of F2 and later generations in rice (Oryza sativa L.) are common and genetically complicated. We used a restriction fragment length polymorphism linkage map and F4 progeny testing to investigate hybrid sterility and hybrid breakdown in a cross between "widely compatible" O. sativa ssp. japonica cultivar Lemont from the Southern U.S. and ssp. indica cul...

ATSON and CASPARI (1960) developed a mathematical model to study the VU behavior of cytoplasmic pollen sterility in populations. They dealt with a population possessing two kinds of cytoplasm and pollen sterility resulting from an interaction of the recessive homozygote with one of the cytoplasms. Under these conditions the frequencies of the maternally transmitted cytoplasms remained unchanged...

Several derivatives of 5-O-mycaminosyltylonolide substituted at C-23 have been prepared; these are 23-deoxy-23-C-methylene (3), 23-deoxy-23-C-(methoxycarbonylmethylene) (5), 23-deoxy-23-C-(ethoxycarbonylmethylene) (7), and 23-deoxy-23-C-(butoxycarbonylmethylene) (9), 23-deoxy-23-C-[(2E)-3-(ethoxycarbonyl)-2-propenylene] (11), and 23-deoxy-23-(dimethylaminoimino) (13), and 14-de(hydroxymethyl)-1...

Rice yield can be increased in many ways such as developing new high yielding varieties or adopting proper agronomic management to the existing varieties. Proper fertilization is an important management practice to increase rice yield. Proper fertilization can markedly increase the yield and improve the quality of rice [1]. Nitrogenous fertilizer has immense effect on rice yield throughout the ...

Comparative genetic mapping provides insights into the evolution of the reproductive barriers that separate closely related species. This approach has been used to document the accumulation of reproductive incompatibilities over time, but has only been applied to a few taxa. House mice offer a powerful system to reconstruct the evolution of reproductive isolation between multiple subspecies pai...

Bioluminescence measurement significantly improved the accuracy, sensitivity, precision, and reliability of the current visual endpoint determination for the USP sterility test and eliminated the day 7 transfer/dilution step required for testing suspension products. Thirteen strains of bacteria and fungi (representing potential contaminants in sterile products), three pharmaceutical suspension ...