Target weeds

Younger barnyard grass is effective, but the resistant barnyard grass (such as barnyard, red root, etc.) and moleplant seed is not effective

It is effective on old barnyard grass, kotgrass, rice plum powel, and some broad-leaved grass (ciderage, Monochoria vaginalis, Alligator weed) had a certain control effect. Has no high effect on resistant paspalum moleplant seed.

Metamifop has good control effect on most of the barnyard grass, crabgrass and goose grass, Especially, the resistant paspalum had better control effect, Can control moleplant seed.

Safety performance

Penoxsulam is very safe for rice, and it has no significant effect on plant height, heading time and yield of any rice varieties when sprayed at 2-3 leaf stage (direct seeding). Ultrahigh dose can inhibit the growth of rice root in the early stage, but it can recover quickly without affecting the yield.

Bispyribac-sodium was safer for indica rice, but more sensitive to japonica rice and waxy rice. After spraying, Some rice varieties showed slight or serious chlorosis and whitening, but usually recovered within 7 to 10 days, and had no effect on rice yield.

The administration time of Bispyribac-sodium was strictly required, requiring that it should be used after three leavesand one heart in indica rice and four leaves and one heart in japonica rice, and it should not be used at the booting stage of rice.

Metamifop must be used after 3 leaves and 1 heart of japonica rice, indica rice must be used after 4 leaves and 1 heart of rice, low temperature or too young leaf age will cause serious drug damage. In terms of the safety of rice, Metamifop was poor, while Bispyribac-sodium was weaker than Penoxsulam.

Suitable temperature

Penoxsulam has no strict requirement on temperature, so it is a better choice for early rice at low temperature. 

Bispyribac-sodium required temperature between 25 ~ 35℃ is appropriate, when the temperature is lower than 15℃ the effect is not ideal, and may lead to drug harm;

When the temperature above 30℃, the effect of Metamifop is the best, low temperature or too young leaf age, will produce serious harm.

Effect

When used properly, Penoxsulam can achieve more than 90% of the effect of grass killing

The suitable dosage of Bispyribac-sodium can reach more than 95%.

Metamifop only had an obvious effect on the parts above the nodes, which could achieve 99% weeding effect, but had no obvious effect on the growth points and roots.

Speed

3 ~ 5 days

7 ~ 10 days, but it takes about 15 days for the weeds to die when the temperature is below 20℃.

15 days

Conclusion 

Penoxsulam is suitable for rice with 2 leaves and 1 heart at low temperature.      

Bispyribac-sodium is suitable for rice after 3 leaves and 1 heart at normal temperature.      

Metamifop is suitable for control of resistant barnyard grass or when use Penoxsulam is not affect well.