a s a d a R a o ,3 M . H. M e n g e s h a ,3 a n d D . E . B r i n k 2Paspalum scrobiculatum is widely distributed in damp habitats across the Old World tropics. It is harvested as a wild cereal in w est Africa and in India. The species was dom esticated in India som e 3,000 yr ago. It is grown in India from Kerala and Tamil N adu in the south, to Rajasthan, U ttar Pradesh and West Bengal in the north. K odo millet is variable but lacks racial differentiation. The species was apparently dom esticated across its range o f present-day cultivation. Hybridization with wild P. scrobiculatum, which commonly invades fields o f kodo millet, obscures racial differentiation. W eedy kodo is harvested with the crop, making it difficult to distinguish wild and cultivated com plexes o f P. scrobicula tum. Wild, w eed and cultivated kinds m erge in all characters studied.The genus Paspalum (Gramineae) includes some 400 species that extend across the warmer regions of the world. Paspalum scrobiculatum L. occurs throughout the Old World tropics. It is cultivated in India. Cultivated plants are grown as annuals, but many cultivars root at the lower nodes and, under favorable con ditions, continue to produce culms after the older shoots have flowered and ma tured their inflorescences. Wild P. scrobiculatum is perennial. In southern India wild plants invade fields of planted kodo millet, and the spikelets of these weeds are often as large as those of the crop.Paspalum scrobiculatum occurs in moist or shady places across the tropics and subtropics of the Old World. The species is recognized, as demonstrated by Clayton (1975), to include the African P. orbiculare Forst. f., P. polystachyum R. Br., and P. cartilagineum Presl with usually smaller spikelets (1.8-2.5 mm long) than those of Indian wild specimens (2.5-3.5 mm). These taxa merge com pletely, not only in spikelet morphology, but also in overall inflorescence mor phology and vegetative traits. Plants are slender to stout, up to 90 cm tall, and often root from the lower nodes. Leaf blades are linear, glabrous or pubescent, up to 40 cm long, with the basal leaf sheaths glabrous or pilose. Inflorescences are composed of rarely more than 5 racemes (3-7) that are alternately arranged on a short to elongated primary axis. Racemes are up to 13 cm long, with the subsessile spikelets arranged in 2 rows along one side of a flattened rachis. Spike lets are glabrous, orbicular to broadly elliptic in outline, conspicuously plano convex, 1.8-3.5 mm long, and never awned. The lower glume is absent, and the upper glume is as long as the spikelet. The lower lemma is almost flat, more or less membranaceous and without a palea or floret. The upper lemma is crustaceous, often brown and shiny when grains are mature, and embraces the crustaceous palea. The grain is elliptic-orbicular in outline and 1.5-2.5 mm long.
Seed protein profiles of nine diploid species (2n = 20), ten tetraploid accessions, two synthetic amphidiploids and two autotetraploids (2n = 40) were studied using SDS-polyacrylamide gel electrophoresis. While the general profiles suggested considerable homology among these taxa in spite of speciation and ploidy differences, appreciable genetic differences were present to support the existing genomic divisions and sub-divisions in the section Arachis. A high degree of relationship was indicated between the two diploid species (A. duranensis containing the A genome and A. batizocoi (ICG 8210) containing the B genome) and tetraploids A. monticola/ A. hypogaea (2n = 40) containing AABB genome. Similar relationships were recorded between the AABB synthetic amphidiploid and the profile obtained from the mixture of protein of A. duranensis and A. batizocoi, suggesting that these two diploid species were the donors of the A and B genome, respectively, to tetraploid A. monticola/A. hypogaea.
SummaryCicer echinospermum, a wild relative of chickpea (Cicer arietinum L.), has traits that can be used to improve the cultivated species. It is possible to obtain successful crosses between the two species, even though their cross progenies have reduced fertility. The reasons for this low fertility could be due to the two species differing in small chromosome segments or at genic level. Another limitation to the use of C. echinospermum at ICRISAT Asia Center is that the species is not adapted to the short photoperiod which prevails during the chickpea cropping season at Patancheru, Andhra Pradesh, India. Future work will include screening the segregating progenies for monitoring traits from both the species through isozyme analysis and to incorporate these into good. agronomic backgrounds following backcrosses.
a s a d a R a o ,3 M . H . M e n g e s h a ,3 a n d D . E . B r in k 2 Two species o f Echinochloa are grown as cereals. Echinochloa crusgalli is native to tem perate Eurasia and was dom esticated in Japan som e 4,000 yr ago. Echinochloa colona is widely distributed in the tropics and subtropics o f the Old World. It was dom esticated in India. Echinochloa colona is m orphologically al lied to E. crusgalli, but hybrids betw een-them are sterile. Echinochloa colona differs consistently from E. crusgalli in having sm aller spikelets with membran aceous rather than chartaceous glum es. H ybrids between wild and cultivated taxa o f E. colona and betw een those o f E. crusgalli are fertile. Cultivated E. colona is variable. It is grown as a cereal across India, Kashm ir and Sikkim. Four m orphological races are recognized, although these do not have geograph ical, ecological or ethnological unity. R ace laxa is confined to Sikkim where races robusta, intermedia and stolonifera are also grown. In India, races robusta, intermedia and stolonifera are often grown as mixtures, and Echinochloa is som etim es grown as a mixture with other cereals, particularly Setaria italica (foxtail millet) or Eleusine coracana (finger millet). The species is p lan ted on p o o r soil, and som e cultivars m ature in less than 2 mo. They hold considerable prom ise as cereals fo r the sem iarid tropics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.