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Bettina Heider Elke Fischer Tanja Berndl Rainer Schultze-Kraft 《Genetic Resources and Crop Evolution》2007,54(3):529-542
Pueraria montana var. lobata and P. phaseoloides originating from tropical Asia and parts of Oceania are ecologically and economically important legumes that are used as
green manure, cover crop or forage plants. Conservation and use of plant genetic resources require an understanding of the
extent and distribution of genetic diversity in any given region. In this study, genetic variation of five P. montana var. lobata and 16 P. phaseoloides accessions was analysed developing a random amplified polymorphic DNA (RAPD) marker methodology for Pueraria species and thereby creating basic data for follow-up research and the development of conservation strategies. Seeds were
collected from native populations in Bac Kan Province, a mountainous region in Northeast Vietnam. P. montana var. lobata presented a high level of variation with 54.3% of the detected markers being polymorphic, whereas P. phaseoloides exhibited an intermediate to high level of variation (45.5%). The P. montana var. lobata accessions clustered in congruence with their eco-geographical origin. For P. phaseoloides no correspondence between sampling sites and genetic differentiation was found. Inter-population differentiation was measured
as Jaccard's similarity coefficient (JSC). Mean JSC amounted to 0.35 in P. montana var. lobata and 0.52 in P. phaseoloides. Results are compared to other genetic studies of herbaceous legumes and conservation strategies are suggested. 相似文献
3.
O. Ozbek E. Millet Y. Anikster O. Arslan M. Feldman 《Genetic Resources and Crop Evolution》2007,54(7):1587-1598
The aim of the present study was to assess the genetic variation in several Israeli and Turkish populations of wild emmer
wheat, Triticum turgidum ssp. dicoccoides, the progenitor of most domesticated wheat. Single spikes were collected in 2002 from 60 plants that grew in six different
habitats in Ammiad, northeastern Israel (8–12 plants from each habitat), and in 1998 from 56 plants that grew in seven different
habitats in Diyarbakir, southeastern Turkey (8 plants from each habitat). Seeds were planted in a nursery and DNA was extracted
from every plant and analyzed by the fluorescent-based amplified fragment length polymorphism (AFLP) method. Seven primer
combinations produced 788 discernible loci of which 48.6% were polymorphic in Israel and 40.5% in Turkey. The genetic diversity
estimates P (frequency of polymorphic loci) and He (gene diversity) were higher in Ammiad than in Diyarbakir (means of P = 0.34 and He = 0.13 in Ammiad vs. P = 0.20 and He = 0.08 in Diyarbakir). Ammiad populations contained more unique alleles than Diyarbakir populations. The relative genetic
diversity estimates (θ) values were 0.188 in Ammiad and 0.407 in Diyarbakir, suggesting better differentiation of the populations in Turkey. Genetic
distance was larger between Israeli and Turkish populations than between populations of each country. The data indicate that
the Israeli and Turkish populations are considerably diverged and that the Israeli populations are more polymorphic than the
Turkish ones, having a larger within-populations genetic variation than among-populations one. The significance of the results
in relation to the differentiation pattern of wild emmer in the Near East is discussed. 相似文献
4.
Reciprocal crosses were made between Brassica carinata and its related species Sinapis alba. Pollen germination studies indicated the presence post-fertilization barriers in both ways. Sequential ovary–ovule culture
helped to realize the intergeneric hybrids from the cross S. alba × B. carinata. The F1 obtained was confirmed as a hybrid based on morphology, cytology and isozyme studies. The hybrid was backcrossed to its male
parent and obtained BC1 seeds, which were used to raise BC1 generation. The BC1 generation plants were further backcrossed to B. carinata in order to develop alloplasmic lines. 相似文献
5.
K. Aitken J. Li L. Wang C. Qing Y. H. Fan P. Jackson 《Genetic Resources and Crop Evolution》2007,54(7):1395-1405
Erianthus rockii, a wild relative of sugarcane, is drought and cold tolerant, and both are potentially important agronomic traits to the sugarcane
industry worldwide. As such it is of interest as a source of parental germplasm to sugarcane breeders and is currently being
used in sugarcane introgression programs in both China and Australia. To date morphological characters have been used to verify
the putative hybrids produced. Two crosses were generated between two different Saccharum species and two E. rockii accessions. Over 400 AFLP markers were used to identify the intergeneric hybrid progeny as well as determine hybrid diversity.
Both crosses generated hybrids but efficiency levels were very different and are probably related to the different Saccharum parent used in each cross. Cross 1 was between a Saccharum officinarum and E. rockii and generated 100% hybrid progeny. Cross 2, however, was between a sugarcane hybrid (S. officinarum × Saccharum spontaneum) and E. rockii and only 10% of the progeny were intergeneric hybrids. Inheritance of markers in the progeny was analysed and for both crosses
there were equal numbers of markers from both parents indicating n + n transmission of chromosomes. This is the first verification of E. rockii hybrids with molecular markers. It may now be possible to exploit genes of value from E. rockii in sugarcane breeding programs. 相似文献
6.
Daria Ryabova 《Genetic Resources and Crop Evolution》2007,54(5):973-980
Many crop wild relatives are usually widely distributed species, and in this relation a question arises about selecting populations
of special importance for conservation. Using Rubus idaeus as an example, we propose a compound selection of wild populations for in situ conservation. Twelve raspberry populations
in the Leningrad region have been evaluated from the point of view of their significance for in situ conservation. To exclude the run-wild forms from the evaluation process, we tried to identify them applying a mathematical
model developed by statusmetry method. The constructed model is based on morphological features of leaves of primocanes and
helps to distinguish the wild forms from the cultivated and run-wild ones. The wild raspberry populations were screened for
plants with features useful for cultivated raspberry improvement such as waxy cover presence, yellow fruiting plants, spinelessness,
fruiting primocanes and others. The diversity of wild raspberry populations was assessed by variation of morphological features,
presence of botanical varieties and polymorphism of seed storage proteins. The results of viability status assessment for
the chosen populations reflect the perspectives of their development and permit to determine the strategy and measures for
optimal conservation. 相似文献
7.
S. D. Segura G. Coppens d’Eeckenbrugge C. H. Ocampo P. Ollitrault 《Genetic Resources and Crop Evolution》2005,52(4):455-463
In a general study of banana passion fruit genetic resources, diversity was analyzed in the two main cultigens, P. tripartita
var. mollissima and P. tarminiana, and their closest wild relative, P. mixta, scoring isozyme bands (IDH,PGM,ACP,PGD,DIA,andPRX)
on288 plants from 31 accessions. Polymorphismandallelic richness, Nei diversity indices, and neighbor joining clustering showed
that variation was poor in the cultigens in northern and central Colombia, while P. mixta appeared much more polymorphic.
The populations of P. tripartita var. mollissima and P. mixta from southern Colombia and Ecuador show higher diversity values
and are clearly differentiated from those of central and northern Colombia. This geographic component of variation is even
stronger than the interspecific one, which suggests a close relation and a regular gene flow between these two species. In
contrast, all the accessions of P. tarminiana constitute a clearly differentiated group, even if some introgression with P.
tripartita var. mollissima is also suspected. The high variation observed in the southern region indicates the proximity of
a center of diversity for banana passion fruit and collecting in Ecuador, Peru and Bolivia is recommended. The high diversity
of P. mixta and the evidence of gene flow with P. tripartita var. mollissima constitute a favorable context for the implementation
of in situ conservation strategies. 相似文献
8.
Takaaki Ishii Atsushi Matsumura Sachie Horii Hino Motosugi Andre Freire Cruz 《Biology and Fertility of Soils》2007,44(1):217-222
A greenhouse experiment was conducted to examine the favorable effects of sod culture system with bahiagrass (Paspalum notatum Flügge.) and Vulpia myuros (L.) C. C. Gmel. intercropped with citrus trees on the establishment of the network of arbuscular mycorrhizal (AM) fungus
hyphae in their rhizospheres. Special acrylic root boxes with three compartments were used for the experiment. Four types
of citrus rootstock seedlings, trifoliate orange (Poncirus trifoliata Raf.), sour orange (Citrus aurantium L.), rough lemon (Citrus jambhiri Lush.), and Citrus natsudaidai Hayata, were separately transplanted into one outer compartment in each box, and the seedlings of bahiagrass and V.myuros were separately transplanted into the other outer compartment. An AM fungus, Gigaspora margarita Becker and Hall, was inoculated in the center compartment of each box. Some boxes with both outer compartments without plants
and with some plants in only one outer compartment were also prepared. The box with bare × bare had very low density of AM
hyphae. There were a few hyphae in bare compartments in the boxes of trifoliate orange × bare, sour orange × bare, rough lemon
× bare, and C. natsudaidai × bare. The density of hyphae in the compartments with citrus seedlings and grasses, however, was significantly higher than
in every bare compartment, and the hyphae in the compartments with plants penetrated deeply into the sand. In particular,
the density in the compartments of citrus seedlings increased when bahiagrass or V. myuros was transplanted as a neighboring plant. The percentage of AM fungus colonization in every plant root was high. New spore
formation was observed in compartments with plants, whereas there were few spores in every bare compartment. In particular,
the spore formation in bahiagrass compartments was superior to that in other compartments with plants. Our results suggest
that the network system by AM hyphae is easily discernible in the rhizospheres between citrus rootstocks and bahiagrass or
V. myuros, but bare ground severely inhibits the formation and development of AM hyphal network and reduces the number of AM spores
in the soil. 相似文献
9.
Hong Bo Guo Bao Rong Lu Qian Hong Wu Jia Kuan Chen Tong Shui Zhou 《Genetic Resources and Crop Evolution》2007,54(5):917-924
Genetic diversity of seven cultivated populations of Codonopsis pilosula Nannf. from Longxi County, Gansu Province of China was estimated using randomly amplified polymorphic DNA (RAPD) markers.
The 17 selected RAPD primers amplified 205 polymorphic bands out of a total of 235 (87.2%). Nei’s gene-diversity statistics
and population differentiation parameters based on AMOVA analysis indicated that the cultivated C. pilosula populations remained a high level of genetic diversity with Hs = 0.299 and I = 0.450. A greater proportion of genetic diversity was found within (77%) rather than among (23%) the populations. In addition,
we also detected that populations from different altitudes had a considerable genetic differentiation after 40 years of cultivation
at the same site. Populations from higher altitude had lower genetic diversity than those from lower altitude. Our results
suggested that irregular and sparse cultivation practices, i.e., random collecting, preserving, and planting seeds of the
medicinal species without deliberate selection, might be an efficient way to conserve genetic resources of medicinal plants,
in addition to their effective uses. 相似文献
10.
Zizania latifolia, which belongs to the tribe Oryzeae, has been cultivated for more than 2000 years and has historically been used in China
mainly as an aquatic vegetable. In China, the largest area under cultivation of this plant is located in the regions surrounding
Tai Lake, in the provinces of Jiangsu and Zhejiang. Two main types of cultivars have been developed, in one the shoots can
be harvested only once, in the fall; in the other, the shoots may be harvested twice in the fall and once the following summer.
Z. latifolia can be bred and conserved through clonal propagation as a means of preventing infection of flowering stems by the epiphyte
Ustilago esculenta. At the end of the harvest period, healthy individuals and the plants with black spots in the shoots are removed, and those
with a healthy clone will be identified and selected as ‘seed’ for the next year. 相似文献
11.
Takuro Ito Toshinori Ochiai Hiroki Ashizawa Toshinori Shimodate Takahiro Sonoda Tatsuya Fukuda Jun Yokoyama Toshiaki Kameya Akira Kanno 《Genetic Resources and Crop Evolution》2007,54(5):1063-1071
The genus Asparagus (Asparagaceae) encompasses 100–300 species, including the important vegetable crop, A. officinalis (garden asparagus). Previous attempts to hybridize garden asparagus with A. densiflorus (Kunth) Jessop, with the aim of introducing disease resistance, were unsuccessful because of the failure of endosperm development.
In the present study, reciprocal interspecific hybrids between garden asparagus and A. schoberioides Kunth were generated by hand pollination. The F1 hybrids were analyzed by using both morphological and molecular techniques.
This is the first report describing the production of an interspecific hybrid between garden asparagus at the diploid level
(2n = 2x = 20) and its diploid (2n = 2x = 20) wild relative, A. schoberioides. Morphological characteristics of candidate hybrids were a mixture of those found in the parents, and cytological and RFLP
analyses confirmed that morphologically intermediate plants were indeed diploid hybrids of those two species. In other words,
post-zygotic isolation is not complete between phylogenetically distinct these two species. Our results suggest that other
Asparagus species may be capable of hybridizing with A. officinalis and that introducing wild characters through interspecific hybridization may offer advantages for breeding for novel traits.
Takuro Ito and Toshinori Ochiai authors are contributed equally to this work 相似文献
12.
M. A. Islam A. Meister V. Schubert K. Kloppstech E. Esch 《Genetic Resources and Crop Evolution》2007,54(1):149-156
Curcuma zedoaria populations comprise 2n = 63 chromosomes with three satellite chromosomes showing elongated secondary constrictions. Flow
cytometry results inferred that the 2C nuclear DNA values varied between the populations. The largest genome size was found
in the population Chittagong (mean 3.37 pg) and the lowest in the Birganj population (mean 3.15 pg). RAPD based estimations
of genetic diversity revealed that hilly populations maintain higher genetic diversity, which was also found to be distinct
from plainland and plateauland populations. Genome sizes and genetic diversity values of the populations were positively correlated. 相似文献
13.
Evaluation of perennial wild <Emphasis Type="Italic">Cicer</Emphasis> species for drought resistance
About 90% of chickpea (Cicer arietinum L.) in the world is grown under rainfed conditions where drought is one of the major constraints limiting its productivity.
Unlike the cultivated chickpea, wild Cicer species possesses sources of resistance to multiple stresses; we therefore evaluated perennial wild Cicer species for resistance to drought. C. anatolicum, C. microphyllum, C. montbretii, C. oxydon and C. songaricum were compared with special checks; C. echinospermum, C. pinnatifidum and C. reticulatum and five cultivated chickpeas. After the cultivated chickpeas were killed, accessions were evaluated using a 1–5 scale, where
1 = highly drought resistant (no visible drought effect and full recovery after three successive wiltings) and 5 = highly
drought susceptible (leaves and branches dried out, no recovery at all). All accessions of perennial wild Cicer species were significantly superior to those annual wild species and the cultivated chickpeas including the best drought
tolerant chickpea, ICC 4958 under drought conditions. Perennial wild Cicer species did not only recover after wilting and drying out above ground level, they also tolerated high temperatures up to
41.8°C. But, they do not cross with the cultivated chickpeas. C. anatolicum should be taken account in long term breeding programs because it has closer affinities to the first crossability group than
the others. 相似文献
14.
Genlou Sun 《Genetic Resources and Crop Evolution》2007,54(8):1737-1746
Elymus trachycaulus complex species are known for their morphological variability, but little is known about their genetic basis. The phylogenetic
relationships among the E. trachycaulus complex, and their systematic relation to other species in Triticeae remain unknown. Nucleotide diversity of ribulose-1,5
bisphosphate-carboxylase (rbcL) gene in E. trachycaulus complex species and several other Triticeae was first characterized and compared. A primary conclusion of the present study
is that nucleotide diversity for rbcL gene in E. trachycaulus species was detected with the estimates of nucleotide diversity θ = 0.00039 and π = 0.00043. The estimate of nucleotide diversity
in rbcL gene for species with different genome constitution here ranged from 0.00099 (π) and 0.00099 (θ) for the species with Ns
genome to 0.00226 (π) and 0.00291 (θ) for the species with St genome. The phylogenetic relationships of these species were
assessed using these rbcL sequences. A total of 47 variable positions including 19 parsimony-informative sites were detected among 24 accessions of
18 species/subspecies. The species with St, H/I and Ns genomes well separated from each other, and formed a three distinct
clades with higher bootstrap values support for both Parsimony and NJ analyses. The St genome containing species is sister
group of H/I genome containing species. Our result confirms that Pseudoroegneria is the maternal genome donor to these Elymus species studied here, regardless of their distribution. Elymus trachycaulus complex are more related to each other than to E. glaucescens, E. patagonicus, and E. solandri. This study suggested that Elymus species with StH genomes may form from multiple closely related sets of donors. 相似文献
15.
Gert Poulsen Claus Holten Roland von Bothmer 《Genetic Resources and Crop Evolution》2007,54(5):1105-1115
Dead seeds of a fodder beet cultivar ‘Elvetham’ stored under ambient conditions since 1880 were compared to a homonymous sample
preserved in an on-farm situation in Denmark. DNA was isolated from single seeds and successfully applied to Amplified Fragment
Length Polymorphism (AFLP) analysis of the accessions. Six primer pairs were used to determine the similarity between the
two accessions based on 112 polymorphic bands. Furthermore, similarity among seven cultivars of fodder beets representing
the main types used in Scandinavia at the end of the 19th century was determined. This analysis was based on 152 polymorphic
bands. Differentiation among the seven cultivars was determined to a mean G
ST value of 0.438, while G
ST between the two ‘Elvetham’ accessions was 0.266. A principal coordinate analysis based on jaccards similarity index illustrates
that the two ‘Elvetham’ accessions are different from each other. The differentiation is higher than the value found between
two separate ‘Eckerndorfer’ accessions. The results indicate that the cultivated accession has changed. Additionally, the
value of applying old dead seed material for documentation in gene banks is demonstrated.
During the analysis it was found that DNA isolated from seeds and leaves behaved differently in the AFLP process, however,
the two fractions assigned to their common accession. 相似文献
16.
Ryoichi Ikeda Yoshimi Sokei Inoussa Akintayo 《Genetic Resources and Crop Evolution》2007,54(8):1637-1644
A comparison of breeder seed from different seed sources produced guidelines for multiplication of NERICA (New Rice for Africa)
varieties. Lower percentage detection of offtypes was noted with seed from a breeder than with seed from the Genetic Resources
Unit (GRU) of the Africa Rice Center. The GRU grows breeder seed in the field as bulk populations of varieties and this seed
is multiplied for the foundation seed. Breeders, however, always cultivate the variety in each family with several lines.
In the comparison, each NERICA variety was cultivated as a single plant per hill for easy offtype detection in the field.
Any offtypes or doubtful plants were recorded and immediately discarded. The breeder seed was not always genetically uniform
because it was not yet fixed genetically and included mechanical seed mixture as well as natural mutants. Offtypes were classified
into categories such as chlorophyll mutants, aberrations of plant height, plant types and panicle types, semi- or high sterility,
awnness, apiculous color, leaf sheath color and excessively early plants. The causes of these offtypes were mainly (1) mechanical
seed mixture, (2) segregation in genetically-unfixed material, (3) out-crossing with another variety, or (4) natural mutation.
In 2006, we multiplied foundation seed using used home-saved seed from the 2005 crop harvested after removal of offtypes.
The detection percentage of offtypes decreased compared with the previous year, but the number of semi- or high sterility
plants increased significantly. This review confirms that breeder seed must be maintained with line culture within a family. 相似文献
17.
Christopher M. Richards Michael F. Antolin Ann Reilley Jackie Poole Christina Walters 《Genetic Resources and Crop Evolution》2007,54(4):837-848
Genebanks complement other conservation programs because they preserve genetic diversity needed for future breeding and restoration.
We evaluated efficiency of capturing genetic diversity, using endangered Zizania texana (Texas wild rice) as a model for plants with recalcitrant seeds. This perennial aquatic grass is restricted to 4 km of the
San Marcos River in Texas. An early conservation collection included plants from stands throughout the river, based on the
assumption stands would be unique genotypes. Using microsatellite markers, we found that genetic diversity was concentrated
in five of 15 large, demographically stable stands; 96 stands smaller than 2 m2 contributed no unique alleles. High heterozygosity and few duplicate genotypes suggested that sexual reproduction occurs
more often than presumed. Simulations of stratified sampling of large stands captured all alleles in only 45 individuals,
while random sampling along the river captured much less diversity. The early conservation collection captured as much diversity
as expected from random sampling. Texas wild rice stands resemble a mainland-island metapopulation; our analyses suggest that
stratified sampling maximizes genetic diversity for this population dynamic. Demographic and genetic information is important
for validating the design of efficient ex situ collections and guiding in situ conservation. 相似文献
18.
Jaime Prohens Gregory J. Anderson F. Javier Herraiz Gabriel Bernardello Arnoldo Santos-Guerra Daniel Crawford Fernando Nuez 《Genetic Resources and Crop Evolution》2007,54(3):451-464
Solanum vespertilio Aiton and Solanum lidii Sunding are endemic, endangered wild species from the Canary Islands. These species are of potential value for eggplant (S. melongena) breeding, given that they are part of the secondary genepool of this crop. We study genetic diversity with amplified fragment
length polymorphisms (AFLPs) markers from 5 populations of S. vespertilio (47 samples) and 3 of S. lidii (26 samples). Five related African species (S. dasyphyllum Schumach. et Thonn., S. delagoense Dunal, S. campylacanthum Hochst., S. panduriforme E. Mey, S. aff. violaceum Ortega) were also included in the analysis. A total of 235 AFLP markers included 178 and 156 that were polymorphic in S. vespertilio and S. lidii, respectively. Analysis of genetic distance, phenograms, and principal component plots showed that these rare Canarian species
are differentiated (G
ST = 0.412) from the continental materials and that Solanum vespertilio is more distinct to its African congeners than is S. lidii. There is a relatively high level of differentiation between the two species (G
ST = 0.373), that presumably reflects geographic restrictions (S. lidii to Gran Canaria; S. vespertilio essentially to Tenerife). However, both species have similar levels of total diversity. We speculate that the combination
of the many unusual reproductive features (andromonoecy, zygomorphy, heteranthery and weak enantiostyly in S. vespertilio) help explain genetic diversity that is high for self compatible species. The high genetic diversity may also indicate populations
were larger in the past. A decrease in population size could contribute to the relatively low genetic differentiation among
the populations. The data presented herein provide the foundation for initiation of ex situ and in situ conservation programs
for these wild relatives of eggplant.
This paper is dedicated to the memory of Dr. Richard N. Lester, who made significant contributions to the taxonomy, biosystematics
and conservation of genetic resources of African species of Solanum. 相似文献
19.
N. P. S. Dhillon R. Ranjana Kuldeep Singh I. Eduardo A. J. Monforte M. Pitrat N. K. Dhillon P. P. Singh 《Genetic Resources and Crop Evolution》2007,54(6):1267-1283
Diversity among 36 snapmelon landraces, collected from 2 agro-ecological regions of India (9 agro-climatic sub-regions), was
assayed using RAPD primers, morphological traits of plant habit and fruit, 2 yield-associated traits, pest and disease resistance
and biochemical composition (TSS, ascorbic acid, titrable acidity). Typical differences among accessions were observed in
plant and fruit characteristics and snapmelon germplasm with high titrable acidity and possessing resistance to downy mildew,
Cucumber mosaic virus, Zucchini yellow mosaic virus, Papaya ringspot virus, Aphis gossypii and Meloidogyne incognita was noticed in the collection. RAPD based grouping analysis revealed that Indian snapmelon was rich in genetic variation
and region and sub-region approach should be followed across India for acquisition of additional melon landraces. Accessions
of var. agrestis and var. momordica clustered together and there was a separate cluster of the accessions of var. reticulatus. Comparative analysis of the genetic variability among Indian snapmelons and an array of previously characterized reference
accessions of melon from Spain, Israel, Korea, Japan, Maldives, Iraq, Pakistan and India using SSRs showed that Indian snapmelon
germplasm contained a high degree of unique genetic variability which was needed to be preserved to broaden the genetic base
of melon germplasm available with the scientific community.
N. P. S. Dhillon and Ranjana contributed equally to this work and are considered the first authors. 相似文献
20.
Cultivated tetraploid Gossypium hirsutum L. (Malvaceae) cotton has been characterized as having one flower at a primordia. In a strain (CSH-13) of Gossypium hirsutum cotton, four plants out of 103 had two to three double bolls or twin bolls/plant during 2003–2004 crop season at CICR regional station, Sirsa, Haryana, India. Progeny evaluation in 2004 and 2005 crop seasons indicated that plants raised from seeds harvested from double bolls/twin bolls produced plants bearing double bolls only and plant progeny raised from the seed of single bolls from these mutant plants produced two to three double bolls per plant similar to the parent. Progeny testing revealed that double boll formation is the result of spontaneous mutation and environment does not influence its expression. The mutant is early in maturity by 10–15 days, naked seeded and possesses comparable agronomic characters with normal plants. Another spontaneous mutant of Gossypium hirsutum having more than three appendages originating from primordia.: four bolls one leaf, three bolls one leaf, two bolls two leaves, one boll three leaves were obtained from the population of CISV-13 strain in crop season 2003. These appendage groups have been described as bicolor unit by Clemens Bayer, [Zur Infloreszenzmorphologie der Malvales. Dissertations Botany 212 (1994)] and cluster mutant by Russell and Luther [J Cott Sci 6 (2002) 115]. One to three bolls in a cluster or bicolor unit were observed without formation of seeds and lint. About one-third of the total bolls on the mutant plant were of this type. In progeny testing during 2004 and 2005 crop seasons, this mutant produced plants exclusively with more than three appendages revealing that plants identified in 2003 were due to spontaneous mutation. This mutant was also early and naked seeded. Many of the other characters of the mutant plants were comparable with the wild type plants of the strain. Both the mutants were observed having economic impact due to their better yielding ability as compare to respective parents. 相似文献