81437
A computer simulation showed that with alternating annual use between glyphosate and paraquat , only one field in five would be expected to have glyphosate-resistant annual ryegrass ( " Lolium rigidum " ) after 30 years , compared to nearly 90 % of fields sprayed only with glyphosate .
 Lolium rigidum
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 Lolium rigidum