310 FIELD CROPS FOR THE COTTON-BELT 



381. Fertilization. — The wheat flower possesses two 

 erect plume-like stigmas which surmount the ovulary. 

 There are three stamens each bearing an anther. As the 

 flower develops, the filaments bearing the anthers elongate 

 rapidly, pushing the anthers upward so that they suddenly 

 overturn allowing the pollen to fall upon the stigmas. 

 These expansions and processes take place within the 

 closed flower, and thus the wheat is self-fertilized. After 



■4-40 AM 



4-43 AM 



4-4J AJ>A 



4-47-. AM 



4-55 AM 



5-08 A-JA 



5- 15 AM 



5I8 AM 



10 



Fig. 51. — Illustrating the opening and closing of the wheat flower: 

 1 to 5, opening of the flower; 6 to 8, closing of the flower. In 9, thei 

 flower is shown as closed, only the anther having escaped; in 10 none 

 of the anthers succeeded in passing out of the enveloping chaff. 



fertilization takes place the anthers are pushed outside 

 of the glumes and at this time the wheat is generally 

 recognized as being "in bloom." Rainy weather at the 

 time that fertilization is taking place is said to cause im- 

 perfect fertilization, as the inside of the flower is likely to 

 retain some of the water. 



382. The grain (Fig. 53). — The wheat grain is a uni- 

 locular iridehiscent caryopsis of oblong shape with one end 

 slightly pointed, and with a longitudinal furrow on one side, 

 causing a deep infolding of the pericarp. At the base of the 

 grain opposite the furrow is the small embryo or germ. 



