RDE Abstract of Completed Research

RDE Abstract of Completed Research

Monitoring of Released Micropropagated Plantlets to Different Planters/Recipients (2005)
M.T.D. Alejandrino, C.L. Morales, T.B. Bañas and D.A. delos Santos
Of the seven recipients who have already cutbacked their microplantlets, an average of 79.30% survival rate was observed. The highest survival rate of 98.0% was observed at DMC Farms (Kabankalan City) and Had. Bayabas (Cadiz City) and the lowest was at 30.0 % at ELRO, Had. Valencia (Bais City). ELRO got the lowest survival rate because the microplantlets were unloaded from the truck three (3) days after release which resulted to high mortality of plantlets.
There were not much of pests and diseases except for minimal occurrence of borers, downy mildew and rust which were controlled also by the planters/recipients.
An average of 21.13 lacsas were produced by the different planters/recipients. ELRO, Had. Valencia of Bais City has the lowest production (7.0 lacsas) while Hda Bayabas, Cadiz City had the highest production of 39 lacsas.

Improvement of Phil 56226 through Induced Mutation (2005)
Serrano, V., M. Guevarra , A. Burcer and J. Recuenco
Shoot tips of two commercial varieties Phil 56226 and Phil 8583 were subjected to different doses of gamma irradiation ranging from 2 to 5 kr to induce mutation for smut resistance and improved yield performance.
Selections from the second vegetative mutation generation (MV2) based on smut resistance were multiplied and studied for their stability for two years. After the first ratoon in the preliminary yield test, one selection, Phil 56226-51 showed resistance to smut but with no yield improvement compared with the control. No selections from Phil 85-83 possessed the agronomic traits desired. A wider range of mutagen treatment and larger population may be needed to obtain mutants with desirable characteristics.

Variability of sugarcane smut, Ustilago scitaminea Sydow isolates from five mill districts of Luzon (1999). 46th PHILSUTECH Annual Convention Proceedings. Agnes Casupanan and Marcelo Guevarra The test varieties showed varied reactions to all 13 isolates of U. scitaminea. Isolate from Sta. Rita and Canlubang were the most virulent indexes, producing a mean infection of 35.58 and 37.51 percent; the least virulent were isolates Floridablanca and Arayat with 4.50 and 4.35 percent respectively. Phil 7270 is the most resistant variety, Phil 7544 is intermediate susceptible and Phil 56226 the most susceptible. The most aggressive isolates were those from Floridablanca, San Fernando, Mexico in Pampanga, Lapaz, Tarlac and Tuy, Batangas which showed smut whip symptoms at 30 days after inoculation on Phil 6607, Phil 8013, Phil 56226, Phil 6723, Phil 7779, Phil 7270 and Phil 8093, respectively. Based on host reaction and virulence index of the 13 isolates, four races were detected, the Us-A, Us-B, Us-D and Us-6, Us-A is the most prevalent race consisting of nine isolates, followed by race groups Us-B, Us-D and Us-G of 2, 1 and isolates. Reaction of different sugarcane varieties to different smut isolates from Luzon (1995)
Agnes Casupanan and Reynaldo Sampang

The variability of 13 isolates of U. scitaminea based on virulence and aggressiveness were studied.

The test varieties showed varied virulence to the 14 isolates of U. scitaminea. Sta. Rita, Manaog and Canlubang isolates were the most virulent producing 58.65, 60.77 and 67.33 percent infection on Phil 8093, Phil 7779 and Phil 7228, respectively. The least virulent was Arayat and Floridablanca isolates with 9.93 mean percent infection on Phil 8013, Phil 7270 and Phil 6607.

The most aggressive isolate were those from Floridablanca, San Fernando, Mexico in Pampanga, La Paz, Tarlac and Tuy, Batangas wherein they showed smut whip symptom thirty days after inoculation on Phil 6607, Phil 8013, Phil 56226, Phil 7779, Phil 7270, Phil 8093 and Phil 6723.

Reaction of commercially grown sugarcane varieties to different mosaic isolates from Luzon (1995)
Agnes Casupanan and Reynaldo Sampang

Eight isolates of sugarcane mosaic virus (SCMV) were tested on ten commercial sugarcane varieties.

Phil 6607 and Phil 56226 showed no infection to all the isolates tested. Isolate from Pasumil did not infect the test varieties. Isolate from Tarlac isolate was the most virulent by exhibiting the highest percent infection on Phil 8093 and Phil 8013. The isolate from Banilad was the most aggressive by showing the shortest incubation period.

The ordinary mosaic symptom was exhibited by most of the varieties except for isolates from Nasugbu and Banilad wherein long discrete chlorotic streak on the leaf blade of Phil 8093 and Co 281 were observed.