What will be the weed control efficiency (%) if weed dry matter in weety check is 30 quintals and in treated plot it is 15 quintals/ha?

Some herbicides control weeds by inhibiting photosynthesis. The sequence of reactions involved in the process is: (A) Production of lipid radical and initiation of chain of lipid peroxidation (B) Extraction of hydrogen from unsaturated lipids by triplet chlorophyll and singlet oxygen (C) Oxidation of lipids and proteins (D) Loss of chlorophyll and carotenoids
Choose the correct answer from the options given below:

The allelochemical allyl isothiocyanate is found in the plant:

The phenomenon of one plant having a detrimental effect on another through the production and release of toxic chemicals is termed as:

The herbicide Metsulfuron methyl belongs to the group:

Which of the statement(s) is/are correct? (A) Urea herbicides inhibit photolysis in photosynthesis (B) Triazines inhibit the growth of emerging seedlings (C) Sulfonyl ureas first affect the meristematic tissues resulting into chlorosis and necrosis (D) Paraquat is a systemic herbicide
Choose the correct answer from the options given below:

Match List-I with List-II:

List-I (Group)	List-II (Herbicide)
(A) Phenoxyacetics	(I) 2,4-D
(B) Ureas	(II) MSMA
(C) Triazines	(III) Atrazine
(D) Arsenicals	(IV) Isoproturon

Choose the correct answer from the options given below:

Match List I with List II –

List I		List II
A	Phalaris minor	I. Summer annual
B	Amaranthus viridis	II. Perennial
C	Cynodon dactylon	III. Aquatic
D	Salvinia	IV. Winter annual

Which of the following weeds is a root parasite?

Given below are two statements: Statement I: Orobanche is a phanerogamic plant parasite. Statement II: Orobanche is a root parasite.

Given below are two statements: Statement I: Parthenium was introduced into India from outside. Statement II: India is celebrating Parthenium Awareness campaign to minimise the losses caused by it and to prevent its further spread.