Plant them side by side with semi-dwarf, high-yielding modern varieties.
Yes, these two rice types are not "strange bedfellows". That is, they can grow together, with one’s presence benefiting that of the other.
This was found in studies done by the Asia Rice Foundation (ARF) and the DA-Bureau of Agricultural Research (BAR) in collaboration with the DA-Philippine Rice Research Institute (PhilRice) and DA-Southern Tagalog Integrated Agricultural Research Center (STIARC).
Used in the study were Kasturi and Sampaguita, both aromatic lodging-susceptive rice varieties; and hybrid and improve inbred varieties developed by DA-PhilRice, International Rice Research Institute (IRRI), and SL-Agritech.
The field experiments were done during the 2003-2004 dry season (November 2003-April 2004) and 2004 wet season (June-October 2004).
The research evaluated the effectiveness of genetic diversity deployment to reduce bacterial leaf blight (BLB, a destructive rice disease) in hybrid rice, and to reduce lodging of special high-quality rice varieties and increase their yields.
Results showed that mixed planting of Kasturi with PSB Rc30 was effective in preventing lodging. Kasturi had 80 percent lodging when grown in monoculture. No lodging was observed in any of the plots involving Kasturi and PSB Rc30.
Field trials done at PhilRice in Muñoz, Nueva Ecija, showed that mixing the BLB-susceptible SL-8 hybrid with the resistant variety PSB Rc82 reduced BLB severity to mixture plots with 2:1 plant population ratio of SL-8 and PSB Rc82 by 24 percent; 1:1 by 44 percent; and 1:2 by 53 percent.
In another farm trial involving the mixture of Mestizo 2 hybrid and PR31563-AR-19-3-3, disease severity in the 2:1 plot was also lower by 48 percent; in the 1:1 plot by 61 percent; and in the 1:2 plot by 76 percent compared to the monoculture plots of Mestizo 2.
Regarding yield, Kasturi produced about four tons per hectare when mixed with PSB Rc30, as compared to 2.7 t/ha when planted alone.
"The results," Asia Rice Foundation said, "demonstrated clearly that mixed planting of semi-dwarf high-yielding modern variety with tall lodging-susceptible high-quality traditional variety can prevent lodging and thereby increase the yield of traditional variety, resulting in higher income for the farmers." – RAF