Table 2.
Mean protein content (g 100 embryos-1) of recommended integrated crop management (ICM) as compared with conventional management practice (CM) for cottonseed embryos in 2012 and 2013.
| Year | Soil fertility | Integrated management strategies | N rates (kg ha-1) | N application schedule | Plant density (plant ha-1) | Seedling raising method | Protein content | Increase of IMS over CM (%) | P |
|---|---|---|---|---|---|---|---|---|---|
| 2012 | LF | CM | 300 | 120-180-0-0 | 18,000 | ST | 2.01 | ||
| IMS1 | 375 | 75-94-150-56 | 30,000 | SR | 2.38 | 18.38 | <0.05 | ||
| IMS2 | 525 | 105-131-210-79 | 30,000 | ST | 2.65 | 32.16 | <0.05 | ||
| HF | CM | 300 | 120-180-0-0 | 18,000 | ST | 2.35 | |||
| IMS1 | 375 | 75-94-150-56 | 30,000 | SR | 2.43 | 3.35 | ns | ||
| IMS2 | 525 | 105-131-210-79 | 30,000 | ST | 2.68 | 14.18 | <0.05 | ||
| 2013 | LF | CM | 300 | 120-180-0-0 | 18,000 | ST | 2.63 | ||
| IMS1 | 375 | 75-94-150-56 | 30,000 | SR | 2.91 | 10.56 | <0.05 | ||
| IMS2 | 525 | 105-131-210-79 | 30,000 | ST | 3.06 | 16.47 | <0.05 | ||
| HF | CM | 300 | 120-180-0-0 | 18,000 | ST | 2.97 | |||
| IMS1 | 375 | 75-94-150-56 | 30,000 | SR | 3.07 | 3.36 | ns | ||
| IMS2 | 525 | 105-131-210-79 | 30,000 | ST | 3.30 | 11.33 | <0.01 | ||
LF and HF represent the low soil fertility level and high soil fertility level, respectively. CM and IMS represent the conventional management practices and integrated management strategies, respectively. The N application schedules of IMS1 and IMS2 were timed to coincide with growth-driven N demand of cotton plants (see Materials and Methods). ST: Seeds were planted in a nursery bed, and then seedlings were transplanted into the field on May 15th. SR: Seeds were planted with bio-organic fertilizer, and seedlings were transplanted into the field with substrate on May 15th. Probability (P) of significant treatment difference according to a paired t-test; NS, not significantly different at P = 0.05.