Sun hemp seeds

Sun hemp seeds (Crotalaria juncea)

Common names: Sun hemp, Indian hemp, Madras hemp

Local names: Hindi: San, Sonai Manipuri: Chingenjhin Bengali: Shon, Sanpat Malayalam: Chanaka, Vakku Marathi: Tag Oriya: Sanpat Telgu: Gilaka, Shanama, Janumu Kannada: Pundi, Saab Tamil: Vakkunnar

Sun  hemp  is  a  rapid  growing  crop  that  is  used for  fibre  production  in  Indo-Pakistan. Sun hemp originated in India, where it has been grown since the dawn of agriculture. It is also good for use as a green manure in many tropical and subtropical areas in the world  as an organic and nitrogen source. It suppresses weeds, slows soil erosion, and reduces root-knot nematode population. The pods are small and inflated, having stiff hairs. It is commonly grown in India as fodder. Sun hemp seeds after crushing can be fed to cattle but feeding as such is not palatable. This can, however be mixed with other palatable feedstuffs in concentrate mixture for feeding of cattle.

Nutritive value

Sun hemp seed contains 71% TDN and 40.3% CP. The lysine and methionine content is 4.7 and 1.7% (on protein basis), respectively.

Deleterious factor

Sun hemp contains pyrrolizidine alkaloids, which are converted by oxidases or cytochrome P450 system of the liver into  potent toxins (Mannetje, 2004). Seeds also contain trypsin inhibitor and ‘Retusamine-N-oxide’ - an alkaloid (Chaudhury et al., 2005).


Intake of sun hemp hay by cattle should be restricted to about 10% of their diet (Reddy et al. 1999).