Mineral fertilizers and plant growth retardants: Its effects on cottonseed yield; its quality and contents

Figures & data

Table 1. Physical and chemical properties of the soil used in I and II seasons

Season	I	II
Soil texture
Clay (%)	43.0	46.5
Silt (%)	28.4	26.4
Fine sand (%)	19.3	20.7
Coarse sand (%)	4.3	1.7
Soil texture	Clay	Loam
Chemical analysis
Organic matter (%)	1.8	1.9
Calcium carbonate (%)	3.0	2.7
Total soluble salts (%)	0.13	0.13
pH (1:2.5)	8.1	8.1
Total nitrogen (%)^a	0.12	0.12
Available nitrogen (mg kg^−1 soil)^b	50.0	57.5
(1% K2SO4, extract)
Available phosphorus (mg kg^−1 soil)	15.7	14.2
(NaHCO3 0.5 N, extract)
Available potassium (mg kg^−1 soil)	370.0	385.0
(NH4OAC 1 N, extract)
Total Sulfur (mg kg^−1 soil)	21.3	21.2
Calcium (meq/100 g)	0.2	0.2
(with Virsen, extract)

Notes: The Physical analysis (soil fraction) added to the organic matter, calcium carbonate, and total soluble salts to a sum of about 100% (Sawan et al., 2009).

^a Total nitrogen, i.e. organic N + inorganic N.

^b Available nitrogen, i.e. NH₄⁺ _& NO₃^-.

Table 2. Range and mean values of the weather variables recorded during the growing seasons (April–October)

Weather variables	Season I		Season II		Overall date (Two seasons)
	Range	Mean	Range	Mean	Range	Mean
Max temp [°C]	20.8–44.0	32.6	24.6–43.4	32.7	20.8–44.0	32.6
Min temp [°C]	10.4–24.5	19.4	12.0–24.3	19.3	10.4–24.5	19.3
Max–Min temp [°C]	4.7–23.6	13.2	8.5–26.8	13.4	4.7–26.8	13.3
Sunshine [h d^−1]	0.3–12.9	11.1	1.9–13.1	11.2	0.3–13.1	11.1
Max hum [%]	48–96	79.5	46–94	74.7	46–96	77.2
Min hum [%]	6–48	30.1	8–50	33.0	6–50	31.5
Wind speed [m s^−1]	0.9–11.1	5.2	1.3–11.1	5.0	0.9–11.1	5.1

Source: Sawan et al. (2009).

Table 3. Effect of P rate and foliar application of Zn and Ca on cottonseed yield, seed index, seed oil, seed protein, oil and protein yields

Treatments			Cottonseed yield (kg ha^−1)^a	Seed index (g)^a	Seed oil (%)^b	Oil yield (kg ha^−1)^b	Seed protein (%)^b	Protein yield (kg ha^−1)^b
P2O5 rate (kg ha^−1)
Control		44	1,837.1	10.19	19.67	361.6	22.35	410.6
		74	2,043.5	10.40	19.86	406.0	22.38	457.5
L.S.D. 0.05^c			41.2	0.05	–	–	–	–
S.E.^d			–	–	0.09	22.2	0.01	23.4
Zn rate (ppm)
Control		0	1,860.2	10.24	19.59	364.5	22.22	413.4
		40	2,020.4	10.36	19.94	403.0	22.51	454.7
L.S.D. 0.05^c			41.2	0.05	–	–	–	–
S.E.^d			–	–	0.17	19.2	0.14	20.6
Ca rate (ppm)
Control		0	1,807.1	10.16	19.74	356.8	22.43	405.3
		20	1,934.6	10.31	19.76	382.7	22.36	432.9
		40	1,992.7	10.34	19.75	394.2	22.34	445.5
		60	2,026.8	10.37	19.82	401.3	22.34	452.4
L.S.D. 0.05 ^c			58.2	0.07	–	–	–	–
S.E.^d			–	–	0.01	9.7	0.02	10.3

^a Combined statistical analysis from the two seasons.

^b Mean data from a four replicate composite for the two seasons.

^c L.S.D. = Least significant differences.

^d S.E. = standard error (Sawan et al., 2001b).

Table 4. Effect of P rate and foliar application of Zn and Ca on seed oil properties^a

Treatments		Refractive index	Acid value	Saponification value	Unsaponifiable matter (%)
P2O5 rate (kg ha^−1)
Control	44	1.4688	0.1332	192.9	0.3575
	74	1.4691	0.1327	191.5	0.3662
S.E^b		0.0001	0.0002	0.7	0.0043
Zn rate (ppm)
Control	0	1.4687	0.1331	192.4	0.3538
	40	1.4692	0.1328	192.0	0.3700
S.E^b		0.0002	0.0001	0.2	0.0081
Ca rate (ppm)
Control	0	1.4689	1.1340	194.9	0.3550
	20	1.4688	0.1330	191.4	0.3575
	40	1.4688	0.1324	191.3	0.3650
	60	1.4692	0.1324	191.2	0.3700
S.E^b		0.0001	0.0003	0.9	0.0034

^a Mean data from a four replicate composite for the two seasons.

^b S.E. = standard error (Sawan et al., 2001b).

Table 5. Effect of P rate and foliar application of Zn and Ca on the relative percentage of saturated fatty acids^a

Treatments		Relative % of saturated fatty acids
		Capric	Lauric	Myristic	Palmitic	Stearic	Total
P2O5 rate (kg ha^−1)
Control	44	0.0812	0.1212	0.5100	21.65	1.844	24.206
	74	0.0688	0.1538	0.2612	19.95	1.746	22.180
S.E^b		0.0062	0.0163	0.1244	0.85	0.049	1.013
Zn rate (ppm)
Control	0	0.0500	0.0988	0.3912	21.67	1.752	23.962
	40	0.1000	0.1762	0.3800	19.93	1.838	22.424
S.E^b		0.0250	0.0387	0.0056	0.87	0.043	0.769
Ca rate (ppm)
Control	0	0.1375	0.2575	0.5025	22.36	2.090	25.347
	20	0.0600	0.1100	0.2900	21.15	1.742	23.352
	40	0.0300	0.0825	0.3000	19.59	1.090	21.092
	60	0.0725	0.1000	0.4500	20.09	2.258	22.970
S.E^b		0.0226	0.0404	0.0534	0.61	0.258	0.872

^a Mean data from a four replicate composite for the two seasons.

^b S.E. = standard error (Sawan et al., 2001b).

Table 6. Effect of P rate and foliar application of Zn and Ca on the relative percentage of unsaturated fatty acids^a

Treatments		Relative % of unsaturated fatty acids			TU/TS^b ratio
		Oleic	Linoleic	Total
P2O5 rate (kg ha^−1)
Control	44	21.89	53.90	75.79	3.13
	74	21.91	55.91	77.82	3.51
S.E^c		0.01	1.00	1.01	0.19
Zn rate (ppm)
Control	0	21.70	54.33	76.03	3.17
	40	22.09	55.48	77.57	3.46
S.E^c		0.19	0.57	0.77	0.14
Ca rate (ppm)
Control	0	21.34	53.31	74.65	2.94
	20	22.26	54.38	76.64	3.28
	40	22.00	56.90	78.90	3.74
	60	22.00	55.02	77.02	3.35
S.E^c		0.19	0.75	0.87	0.16

^a Mean data from a four replicate composite for the two seasons.

^b TU/TS ratio = (total unsaturated fatty acids)/(total saturated fatty acids).

^c S.E. = standard error (Sawan et al., 2001b).

Table 7. Effect of soil application of N and foliar application of K and mepiquat chloride (MC) on the yield, 100-seed weight, oil and protein of the cotton

Treatments	Cottonseed yield (kg ha^−1)^a	100-seed weight (g)^a	Seed oil (%)^b	Oil yield (kg ha^−1)^b	Seed protein (%)^b	Protein yield (kg ha^−1)^b
N rate (kg ha^−1)
95.2	1862.4	10.09	19.73	367.5	22.24	414.2
142.8	2105.0	10.32	19.60	413.0	22.44	472.2
L.S.D. 0.05^c	78.7	0.07	–	–	–	–
S.D.^c	–	–	0.16	33.6	0.11	35.5
K rate (g ha^−1)
0	1804.4	10.03	19.49	351.6	22.32	402.9
319	1985.2	10.19	19.61	389.3	22.32	443.1
638	2047.7	10.27	19.73	404.2	22.34	457.7
957	2097.6	10.32	19.83	415.8	22.37	469.3
L.S.D. 0.05^c	111.4	0.10	–	–	–	–
S.D.^c	–	–	0.12	35.0	0.16	41.8
MC rate (g ha^−1)
0	1891.8	10.13	19.61	371.1	22.31	422.1
48 + 24	2075.6	10.27	19.72	409.4	22.37	464.4
L.S.D. 0.05^c	78.7	0.075	–	–	–	–
S.D.^d	–	–	0.17	36.1	0.15	41.3

^a Combined statistical analysis from the two seasons.

^b Mean data from a four replicate composites for the two seasons.

^c L.S.D. = least significant differences.

^d S.D. = standard deviation was used to conduct t-test to verify the significance between every two treatment means at 0.05 level (Sawan et al., 2007b).

Table 8. Effect of N rate and foliar application of K and mepiquat chloride (MC) on seed oil properties^a

Treatments	Refractive index	Acid value	Saponification value	Unsaponifiable matter (%)	Iodine value
N rate (kg ha^−1)
95.2	1.4684	0.1339	190.8	0.3762	128.9
142.8	1.4695	0.1313	189.7	0.3913	131.1
S.D.^b	0.0011	0.0025	1.4	0.0178	3.3
K rate (g ha^−1)
0	1.4682	0.1352	190.8	0.3675	125.8
319	1.4689	0.1337	190.1	0.3825	130.3
638	1.4692	0.1315	190.3	0.3875	131.6
957	1.4694	0.1300	190.1	0.3975	132.4
S.D.^b	0.0012	0.0021	1.5	0.0170	2.5
MC rate (g ha^−1)
0	1.4683	0.1331	190.6	0.3750	128.3
48 + 24	1.4696	0.1321	189.9	0.3925	131.7
S.D.^b	0.0011	0.0028	1.6	0.0172	3.0

^a Mean data from a four replicate composites for the two seasons.

^b S.D. = standard deviation (Sawan et al., 2007b).

Table 9. Effect of N rate and foliar application of K and mepiquat chloride (MC) on the relative percentage of saturated fatty acids^a

Treatments	Relative % of saturated fatty acids
	Capric	Lauric	Myristic	Palmitic	Stearic	Total
N rate (kg ha^−1)
95.2	0.068	0.068	0.691	21.77	2.157	24.753
142.8	0.069	0.067	0.645	20.18	2.969	22.934
S.D.^c	0.009	0.006	0.451	1.44	0.470	2.283
K rate (g ha^−1)
0	0.077	0.074	1.307	22.40	2.602	26.467
319	0.072	0.070	0.675	21.02	1.955	23.792
638	0.065	0.063	0.350	20.52	1.905	22.903
957	0.061	0.062	0.340	19.96	1.790	22.212
S.D.^c	0.006	0.004	0.180	1.47	0.369	1.925
MC rate (g ha^−1)
0	0.074	0.065	0.775	21.97	2.336	25.221
48 + 24	0.064	0.069	0.561	19.98	1.790	22.465
S.D.^c	0.007	0.006	0.437	1.29	0.382	1.998

^aMean data from a four replicate composite for the two seasons.

^bTU/TS ratio = (total unsaturated fatty acids)/(total saturated fatty acids).

^cS.D. = standard deviation (Sawan et al., 2007b).

Table 10. Effect of N rate and foliar application of K and mepiquat chloride (MC) on the relative percentage of unsaturated fatty acids^a

Treatments	Relative % of unsaturated fatty acids			TU/TS^b ratio
	Oleic	Linoleic	Total
N rate (kg ha^−1)
95.2	21.59	53.65	75.24	3.069
142.8	22.99	54.08	77.06	3.397
S.D.^c	1.35	1.14	2.28	0.403
K rate (g ha^−1)
0	21.26	52.26	73.53	2.790
319	22.11	54.10	76.20	3.228
638	22.60	54.50	77.09	3.390
957	23.18	54.60	77.78	3.523
S.D.^c	1.37	0.63	1.92	0.351
MC rate (g ha^−1)
0	21.27	53.51	74.77	2.974
48 + 24	23.31	54.22	77.53	3.451
S.D.^c	1.09	1.10	1.99	0.349

^aMean data from a four replicate composite for the two seasons.

^bTU/TS ratio = (total unsaturated fatty acids)/(total saturated fatty acids).

^cS.D. = standard deviation (Sawan et al., 2007b).

Sawan, Z. M., Fahmy, A. H., & Yousef, S. E. (2009). Direct and residual effects of nitrogen fertilization, foliar application of potassium and plant growth retardant on Egyptian cotton growth, seed yield, seed viability and seedling vigor. Acta Ecologica Sinica, 29, 116–123.10.1016/j.chnaes.2009.05.008

 Google Scholar

Sawan, Z. M., Hafez, S. A., & Basyony, A. E. (2001b). Effect of phosphorus fertilization and foliar application of chelated zinc and calcium on seed, protein and oil yields and oil properties of cotton. The Journal of Agricultural Science, 136, 191–198.10.1017/S0021859601008644

 Web of Science ®Google Scholar

Sawan, Z. M., Hafez, S. A., Basyony, A. E., & Alkassas, A. R. (2007b). Nitrogen, potassium and plant growth retardant effects on oil content and quality of cotton seed. Grasas Y Aceites, 58, 243–251.

 Web of Science ®Google Scholar