Glasshouse experiments were conducted from March to July 2003 to determine the effects of sowing depth, and the time, duration, and depth of flooding on the emergence, survival, and growth of Fimbristylis miliacea (L.) Vahl. The treatments that were evaluated in the first experiment were three seeding depths (0, 0.5, and 1.0 cm), while in the second experiment, three flooding depths (saturated soil with no standing water and soil with water depths of 5 and 10 cm) and three flooding durations (7, 14, and 21 days from sowing) were evaluated. In the third experiment, three flooding depths (saturated soil with no standing water, and soil with water depths of 5 and 10 cm) and four flooding regimes (7, 14, 21 or 28 days after sowing [DAS]) were evaluated. Surface seeding gave the highest emergence rate compared to the 0.5 cm and 1.0 cm soil depths. A significantly higher emergence rate was recorded with the saturated conditions than with the flooded conditions. A flooding duration of ≥ 14 days showed a clear trend of reduced emergence with increasing flooding depth. A significantly higher survival rate, plant height, root length, number of leaves, and dry matter were recorded at soil saturation followed by the 5 cm and 10 cm flooding depths when flooding was simulated at 7 and 14 DAS. When the flooding was delayed to 21 and 28 DAS, the 10 cm flooding depth was required to suppress this weed. The results provide sufficient evidence to confirm that from deeper seed burial (1 cm sowing depth), flooding depths of ≥ 5 cm of durations of 14 and 21 days and at the onset of flooding within 14 DAS were effective in suppressing the emergence and growth of F. miliacea. 1995;Begum et al. 1999) and one of the principal weeds in the Philippines, Mashhor

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A glasshouse experiment was conducted at University Putra Malaysia, Serdang, to study the growth pattern of itchgrass collected from 13 locations. The itchgrass was either associated with crops or found along roadsides in six infested estates located in Johor, Kedah, Pahang, Perak, Perlis and Selangor. Significant differences between populations were observed in all variables except in time to seedling emergence. Cluster analysis of the data classified the populations into three major groups. The first group comprised populations from Johor, Pahang and Perak found in association with banana, cocoa and oil palm plantations, or along the roadsides. The second group comprised populations from Kedah, Perlis and Selangor found in association with maize, upland rice, rubber, sugar cane and tobacco plantations. The third group was a distinct population found only along roadsides at Padang Kartong, Perlis. Principal component analysis was performed to determine the growth characteristics that separated the groups. The results showed that plant height, number of leaves, number of seeds/plant, secondary culm diameter and the weight of 100 intact or dehulled seeds were the most significant characteristics that differentiated the groups. The study provided strong evidence of the existence of three itchgrass groups in Peninsular Malaysia.

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Direct seeding has some advantages compared to transplanting system in rice, however there are some constraints need to be addressed. One  constraint generally faced in the wet seeded rice is poor stand  establishment. The experiment was conducted to improve seedling  establishment by using selected growth regulators. Seeds of four rice  cultivars, i.e. Memberamo, Widas, MR 84, and MR 219 were treated with  GA3 (gibberellic acid-3) of 25, 50, and 100 mg 1-1, and IBA (indole-3  butyric acid) of 10, 20, and 40 mg l-1. Results showed that cultivar  response to GA3 was similar in all parameters observed, however the response of cultivars to IBA was different at the initial stage. In Indonesian cultivars (Memberamo and Widas), shoot length of IBA treated seedlings was comparable to the control, but the IBA treated seedlings of  Malaysian cultivars (MR 84 and MR 219) had slightly shorter shoots   compared to the control. GA3 as seed treatment induced favorable early emergence and shoot growth in the initial stage, but the shoots were  etiolated and resulted in susceptible to lodging even in the vegetative  stage. In comparison, exogenous application of IBA resulted in high number of adventitious roots contributing towards better establishment of seedling with broader and greener leaves. The growth regulator was lost its  effect by 2 or 3 weeks after sowing. All IBA concentrations also did not  show any significant differences on growth parameters or have any detrimental effect on grain yield in all cultivar tested. IBA 10 mg l-1 was  sufficient in providing the required improvement in the rice seedlings.