Cytoplasmic male sterility in Vicia faba L.

Summary In many higher plants, nucleo-cytoplasmic interactions lead to pollen abortion. In Vicia faba, cytoplasmic male sterility is unstable as the cytoplasm appears to shift from a sterile to a fertile state. In this report, five flower phenotypes are defined but the study is focussed on the progenies obtained from intermediate, semi-sterile plants with the same homozygous nuclear constitution during five successive generations. The results could be interpreted by quantitative modifications of at least four different kinds of cytoplasmic determinants.     

Comparative electrophoretical analysis of plasmid-like mitochondrial DNAs in Vicia faba and in some other legumes

Minicircular DNAs found in mitochondria of 6-d-old etiolated seedlings of Vicia faba L. were also present in mitochondria isolated from cell suspension cultures and from green leaves of this plant. These results support the suggestion that the plasmid-like molecules found in mitochondria of V. faba are an essential component of the mitochondrial genome. The minicircular DNAs were, apparently, peculiar for the species V. faba since they were found in all three cultivars of this species which were studied. The distribution pattern of plasmid-like DNAs in Vicia villosa L. was completely different and mitochondria from Medicago sativa L. also contained specific minicircular DNAs. Thus, minicircular DNAs are typical for the mitochondrial genomes of several legumes and different plant species have their specific mitochondrial plasmid-like DNAs     

Pollen development in male sterile mangosteen (Garcinia mangostana L.) and male fertile seashore mangosteen (Garcinia celebica L.)

Protoplasma - Mangosteen (Garcinia mangostana L.) is an economically important tropical fruit, yet the reproductive biology of this dioecious plant is complex. Male trees are not known, and female...     

Mitochondrial Arginase Activity from Cotyledons of Developing and Germinating Seeds of Vicia faba L

Differential and sucrose density gradient centrifugation established that about 80% of the total arginase activity (EC 3.5.3.1) in cotyledons of germinating broad bean seeds (Vicia faba L.) was present in the mitochondrial fraction. The mitochondrial arginase activity was enhanced considerably by exposure to osmotic shock, by freezing and thawing, or by Triton X-100 treatment. About 10% of the total arginase activity was recovered from the 40,000g supernatant fraction. During seed maturation, arginase activity in the cotyledons decreased to about one-third of its maximal activity, while increasing over 10-fold during subsequent germination. The time courses of mitochondrial arginase, succinate oxidase, and succinate dehydrogenase activities differed considerably during germination.     

Differences on the microsporogenesis and tapetal development of male fertile and cytoplasmic male sterile pepper (Capsicum annuum L.)

To clarify the time and cause of pollen abortion, differences on the microsporogenesis and tapetum development in the anthers of male fertile maintainer line and cytoplasmic male sterile (CMS) line pepper were studied using transmission electron microscopy. The results showed that CMS line anthers appeared to have much greater variability in developmental pattern than male fertile maintainer line ones. The earliest deviation from normal anther development occurred in CMS line anthers at prophase I was cytomixis in some microspore mother cells (MMCs), and vacuolisation in tapetal cells. Then, MMCs in CMS line anthers developed asynchronously and a small part of ones at the different stage degenerated in advance appearing to have typical morphological features of programmed cell death (PCD). Most MMCs could complete the meiosis, but formed non-tetrahedral tetrad microspores with irregular shape and different size and uncertain number of nuclei, and some degenerated ahead of time as well. Tapetal cells in CMS line anther degenerated during meiosis, and were crushed at the tetrad stage, which paralleled the collapse of pollens. Pollen abortion in CMS line anthers happened by PCD themselves, and the premature PCD of tapetal cells were closely associated with male sterility.     

Mitochondrial genome diversity in connection with male sterility in Allium schoenoprasum L.

Mitochondrial genome diversity in chives (Allium schoenoprasum L.) was investigated with respect to different forms of male sterility. Cytoplasmic male-sterile (CMS) and restored genotypes of the known CMS system, compared to plants of the wi-, the st1- and the st2-sterility types and additional fertile plants of different origin were examined by means of RFLP analyses using mitochondrial gene probes. Besides the (S)-cytoplasm of the CMS system four additional cytoplasms were distinguished that differed in the organisation of their mitochondrial genomes. There is consequently a high degree of variability of the mitochondrial genome in chives, especially when compared with the closely related onion. A possible function of the atp9 gene in generating the different cytoplasm types of chives is discussed in relation to the origin of known CMS sequences in other plant species. The existence of different cytoplasm types offers the opportunity for further characterisation of the wi-, st1- and st2-sterility systems with respect to cytoplasmic factors which might be causally related to them. Whether these new sterilities are CMS or GMS (genic male sterilities) is of interest to plant breeders in order that restrictions on the genetic basis used in hybrid seed production be avoided. Received: 6 July 1999 / Accepted: 6 September 1999     

Acid phosphatase changes associated with development of male sterile and fertile maize (Zea mays L.)

Free and bound acid phosphatase were investigated biochemically and electrophoretically in male sterile and fertile plants. Scutella at the 72-hr seedling stage and anthers with enclosed reproductive tissue at the premeiosis, meiosis, and mature developmental stages were tested. Biochemical data show that while the total amount of free acid phosphatase behaved similarly in fertile and sterile plants, specific activities decreased in fertile plants and remained unchanged or increased in sterile plants. Total amounts of bound acid phosphatase increased significantly in fertile plants while specific activities decreased. In sterile anthers both specific activity and amount of bound acid phosphatase decreased significantly (except cms-S). Electrophoretic results indicated that the basic form of the enzyme was very similar in each location.Published with the approval of the Director of the West Virginia Agricultural Experiment Station as Scientific Paper No. 1573. Based in part on a dissertation by C. V. W. submitted to the Division of Plant Science, West Virginia University, Morgantown, West Virginia.     

Identification of mitochondrial plasmid-like DNAs in Picea abies (L.) Karst.

The Norway spruce (Picea abies (L.) Karst.) mitochondrial DNA has been extracted from embryonal suspensor masses. In addition to a master chromosome, a family of plasmid-like DNAs were identified. These latter shared cross homologies but had no evident sequence homology with the master chromosome. The occurrence of mitochondrial plasmid-like DNAs was investigated in trees from different provenances. A vast majority of trees displayed extrachromosomal DNA elements of variable stoechiometry. For some trees, the sequences homologous to the extrachromosomal DNA elements were found associated with high molecular weight DNA. Received: 9 July 1997 / Revision received: 29 January 1998 / Accepted: 29 November 1998     

Mitochondrial DNA mutations and male infertility

Infertility can be defined as difficulty in conceiving a child after 1 year of unprotected intercourse. Infertility can arise either because of the male factor or female factor or both. According to the current estimates, 15% of couples attempting their first pregnancy could not succeed. Infertility is either primary or secondary. Mitochondria have profound effect on all biochemical pathways, including the one that drivessperm motility. Sperm motility is heavily dependent on the ATP generated by oxidative phosphorylation in the mitochondrial sheath. In this review, the very positive role of mitochondrial genome's association with infertility is discussed.     

Somatic embryogenesis in Vicia faba L.

The paper describes a method of somatic embryo induction in callus and suspension cultures of Vicia faba L. Callus was induced from immature cotyledons (green maturity stage) of white-flowering horse bean lines cultured on L2 medium (Phillips and Collins 1979) supplemented with 1% sucrose, 0.7% agar and different concentrations of 2,4-dichlorophenoxyacetic acid. The medium with 2.5 M 2,4-Dichlorophenoxyacetic acid was found optimum for embryogenic callus induction. Somatic embryos developed after transfer of the callus to media lower or zero 2,4-Dichlorophenoxyacetic acid and increased level of sucrose (2.5%). The release of somatic embryos from the callus was more apparent after transfer to liquid medium. There were various stages of somatic embryo development, i.e. globular, heart-shaped and torpedo ones.     

Liver and muscle proteolytic activity in male growing rats fed a field bean (Vicia faba L.) diet

Total liver cathepsin A and D and gastrocnemius acid proteolytic activities have been evaluated in male growing rats fed ad libitum over periods of 15 and 30 days on 20%-protein diets containing either casein or raw field bean (Vicia faba L.) as protein sources. It has been found that, compared to the control casein-fed rats, those fed the legume diet exhibited a marked reduction (p less than 0.05) in the rate of growth and protein efficiency rate; liver proteolytic activity increased with ageing in the two dietary treatments and was found to be significantly higher (p less than 0.05) in the legume-fed rats. However, muscle proteolytic activity decreased with ageing and proved significantly increased (p less than 0.05) in the legume-fed rats.     

Rubidium Uptake and Boron Deficiency in Vicia faba L

Removal of boron from the nutrient solution reduced root elongationwithin 24 h in V. faba seedlings. This was accompanied by areduction in rubidium uptake per plant as well as an altereddistribution within the root. Although the uptake by the terminalcentimetre was reduced in boron deficiency, there was littleeffect on older tissue. The proportion of absorbed Rb transportedto the shoot, efflux rates, and other uptake characteristicswere similar for deficient and normal tissue. The reduced uptakeis considered to be a secondary effect associated with the requirementsof boron for root elongation and metabolism.     

Hydroxycinnamic acid amides in fertile and cytoplasmic male sterile lines of maize

Hydroxycinnamic acid (HCA) amides in fertile and cytoplasmic male sterile lines of maize were determined in reproductive organs, developing grains and cobs. HCA amides occurred in large amounts in the anthers of fertile plants (line F7N) and were absent from the anthers of cytoplasmic male sterile lines (lines F7T and F7C). Restoration of fertility was associated with the production of these compounds (line FC31). Considerable variations were observed in the concentrations of HCA amides at different stages of growth and grain maturation. Changes of HCA amides in the grains which were to produce sterile plants followed a pattern similar to that obtained with the grains which were to produce fertile plants. Accumulation of HCA amides was substantially higher in fertile lines whatever their genotype (F7N, FC31 and F7T x FC31) than in sterile lines. Marked changes occurred in the HCA amide content of embryo and endosperm during grain development. Many changes in HCA amides were observed in cobs during development and maturation, but no substantial differences could be observed between fertile and sterile lines.