Fagopyrum 19: 109-110(2002) Short Co mm unication Cercospora[agopyri on buckwheat: a note from India Kalyan Kuma r MONDAL, Surendra Singh RANA, Pankaj SOOD and Yadwinder SINGH Regional Researcn Sianon , CSK Hima chal Pradesh Agricu ltural University . Sang/a . Kinnaur 172 106. Himachal Pradesh, India Received July 29, 2002; accepted in rev ised form September 4, 2002 K ey words: buckwheat, Cercospora , lea f spot and prod uce spores successive ly. Th e conid ia are hyaline, elonga te, filliform, rnuniseptate. broadly rounded at the po int of attach ment to the conidio phore and tape ring slightly towards the apex . The co nidio phc res are 47 micron s thick at the apical end and 58-178 micro ns in length. Th e conidia are 75-2 16 microns lon g and 4.56.5 micro ns wide at the base and 1.4 -3.0 microns wide at the tip. Th e pathogenicity of the causal fungus was proved follow ing Koch 's postulate. Based on a literature reviewed (Chupp, 1953, Ellis, 197 1) the pathogen causing leaf spot of buckw heat closely resemb led Cercospora fagopyri. which has been prev iously reported, from Japa n, C hina and Central Poland (Singh and Thom as, 1978). T here is no repo rt o f this d iseas e on buckwheat from India: hence, the present report constitutes a new recording from Himachal Pradesh, India. Com mon buckwheat t Fagopy non esculentum Moench) and Tartary buckw heat (F. uuaricum Gaertn .) are the traditional crops gro wn widely in the dry temperate regions of Ind ia includ ing Kinnaur, Lahul and Spi ti districts of Himachal Pradesh (Joshi, 1999). The Flour of buckwh eat is used for the preparation of "chillare" which is an unleavened bread fried with "ghee" (butter), a popular triba l dish. T he tende r leaves are used as a leafy vegetable. More over, its impo rtance as a health promoting food (due to the presence of a glucoside rut in) due to its medical action oCstrengthening tbe weakness of cap illary blood vesse ls is well known (McGregor and McKill ic.an, 1952; Singh and Th omas, 1978). During a survey (in the years 2001 and 2002) at the trial fields of the Resea rch Station, Sangla, Kinnaur, Himachal Prad esh, Ind ia alon g with the adjo ining buckw heat gro wing areas, an incidence of leaf spot was observed . Th e disea se infected both species but it was much more severe in F. rararicum than in F. esculentum. The disease is known to infect the plant thro ughou t its gro wing stages; however it reached severe propo rtions in the mon th of June-July (i.e. at the seedling stage of lite crop growth ). T he magn itude of da mage was alarm ing when the co tyledonary leaves are infected resulting in poor stand esta blishme nt of the crop. Considering the devastating nature of the diseas e, an initial study was undertaken with special reference to its sym ptoms and etiology. Th e lower leaves near the gro und were attacked first. The tesiosn First appeared as small, roughly circular areas with an ashen-gray center surrounded by reddish-purple borde rs. Individua l spots are appro ximately 2- 5 mm in d iameter and were scattered on the leave s. When a number o f these spots coalesce, the leaves became wrink led and ultimate ly became dry and fe ll off. Th e central dry portion o f the spo ts became so papery tha t it falls away leaving irregu lar- holes in the leaves (Fig. I ). A detailed microscop ic as well as cultura l study indicated that the mycelium of the causal fungus is septate, dar k and interce llular. Small sclerotial masses form in the host tissu e, giving rise to clusters o f dark colo ured conidiopbores. The se appear mai nly within the ash coloured area o f the spots. The conidia are borne sing ly at the tip of the co nidiophore, which conti nue to grow sympodially Cercospora leaf spot on full-grown lea f (a) and on cotyledonary leaf (b) of buckwheat (F. latarieum Gaertn.) Fig. I . REFERENCES Chupp. C. 1953. A monograph of the fungusGenus Cercospora. Ithaca, New York. Ellis, M_B., 1971 . Dernatiaceous Hyphcmyceres. Commonweal th Myco+ 109 110 Mondal eta!. logical Institute, Kew, Surrey, England. Joshi , B.D.,1999. Status of buckwheat in India . Fagopyrum 16: 7-11. McGregor, W.G. and M.E. McKillican, 1952. Rutin content of varieties of buckwheat. Sci. Agri. 32: 48-51. Singh, H. and T.A. Thomas, 1978. Grain Amaranth, Buckwheat and Chenopods. Indian Council of Agricultural Research , New Delhi, India.