Performance of Four Rice Cultivars Transplanted Monthly over Full Year under Irrigated Conditions in Tanzania

doi:10.1016/S1672-6308(14)60283-3

Abstract

Abstract:

In Tanzania, the phenology and seasonal variations of the yields of different rice cultivars have rarely been studied, especially under fully-irrigated conditions. A trial was conducted to identify the most suitable calendar for rice production in Tanzania under fully-irrigated conditions. Four popular rice cultivars, NERICA1, Wahiwahi, IR64 and TXD306, were transplanted monthly from January to December 2011. The four cultivars recorded similarly higher or lower yields than the annual means when transplanted in July (0.50-0.57 kg/m²) and April (0.07-0.31 kg/m²). A yield-ranking analysis showed that plants transplanted in July was the most productive while those transplanted in April was the least productive, and also revealed a yield-seasonality for irrigated rice in Tanzania, a low-yield season (April-May), a high-yield season (June-August), and an unstable-yield season (September-March). These yield seasons would appear to be closely linked to seasonal temperature variations. When transplanted in April-May, plants were exposed to very low temperatures between panicle initiation and flowering, apparently reducing yield through cold-induced sterility. Those transplanted in June-August prolonged their growth under relatively low temperatures and increased yield through increasing biomass production. In September-March, yield levels varied greatly due to the shortened phenological growth durations at higher temperatures. We conclude that under fully-irrigated conditions in Tanzania, rice should be transplanted in July to ensure the maximum production and yield stability. The yield-seasonality suggests that implementing measures to protect plants from low and high temperature stress at critical phenological stages may allow year-round rice production under fully-irrigated conditions in Tanzania.

Key words: irrigated rice, local variety, phenological response, temperature, yield component, yield performance

Sekiya Nobuhito, Cyril Shayo Aristarick, Kaozya Jacob Mathew, Oizumi Nobuaki, Tomitaka Motonori, Araki Hideki. Performance of Four Rice Cultivars Transplanted Monthly over Full Year under Irrigated Conditions in Tanzania[J]. Rice Science, 2015, 22(2): 71-80.

Figures/Tables 4

References 36

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Month	NERICA1								Wahiwahi
	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI
	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)
January	112	78	27.5	2 149	34	27.2	924	18	116	80	27.5	2 203	36	27	974	18
February	117	82	27.6	2 259	35	25.8	904	20	117	83	27.5	2 286	34	25.8	877	20
March	116	81	27	2 184	35	25	877	19	116	81	27	2 184	35	25	877	19
April	126	84	26	2 187	42	23.3	978	10.5	126	87	26	2 261	39	23.2	905	10.5
May	130	91	24.4	2 222	39	23.8	930	15	144	93	24.4	2 270	51	24.1	1228	16
June	123	88	23.7	2 089	35	24.5	858	13.9	137	87	23.7	2 065	50	24.4	1221	13.9
July	123	89	23.7	2 112	34	25.3	861	14	131	98	23.7	2 327	33	25.1	835	13
August	112	79	24.1	1 907	33	26.2	863	17	116	80	24.1	1 932	36	26.2	943	18
September	110	76	25	1 902	34	26.6	906	17	112	80	25.1	2 007	32	26.7	856	17
October	110	76	26	1 978	34	27.6	940	18	123	91	26.2	2 385	32	27.8	891	18
November	104	70	26.9	1 881	34	28.1	955	18	118	84	27	2 272	34	28.2	959	18
December	110	75	27.6	2 068	35	27.7	971	18	119	82	27.7	2 268	37	27.8	1029	18
Mean	116	81	25.8	2 078	35	25.9	914	16.5	123	86	25.8	2 205	37	26	966	16.6
SD	8	6.3	1.5	132	3	1.6	43	2.7	10	5.9	1.5	136	6	1.6	132	2.8
Month	IR64								TXD306
	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI
	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)
January	123	87	27.5	2 394	36	26.9	967	18	134	100	27.4	2 743	34	26.5	901	19
February	138	102	27.3	2 783	36	25.3	911	19	146	109	27.2	2 961	37	25	924	19
March	125	90	26.8	2 414	35	24.6	863	18	147	113	26.4	2 987	34	23.1	785	10.5
April	147	108	25.4	2 748	39	23.3	908	14	155	118	25.2	2 971	37	23.7	878	14
May	141	101	24.4	2 460	40	24.1	964	13	154	118	24.2	2 855	36	24.5	883	13.9
June	139	103	23.9	2 458	36	24.4	878	17	151	117	24	2 803	34	24.7	838	14
July	140	105	23.8	2 498	35	25.7	901	15	152	117	23.9	2 795	35	26.2	917	18
August	130	97	24.5	2 377	33	26.5	874	18	145	112	24.7	2 771	33	26.8	885	17
September	125	89	25.2	2 242	36	27	973	18	145	110	25.5	2 808	35	27.6	966	18
October	123	88	26.2	2 304	35	27.8	973	18	144	110	26.5	2 918	34	28.2	957	18
November	118	83	27	2 245	35	28.2	986	18	134	99	27.2	2 690	35	27.8	974	18
December	125	90	27.7	2 492	35	27.8	974	18	135	101	27.6	2 787	34	27.6	939	18
Mean	131	95	25.8	2 451	36	26	931	17	145	110	25.8	2 841	35	26	904	16.5
SD	9	8.3	1.5	171	2	1.6	46	1.9	7	7	1.4	97	1	1.7	55	2.7

Month	NERICA1								Wahiwahi
	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI
	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)
January	112	78	27.5	2 149	34	27.2	924	18	116	80	27.5	2 203	36	27	974	18
February	117	82	27.6	2 259	35	25.8	904	20	117	83	27.5	2 286	34	25.8	877	20
March	116	81	27	2 184	35	25	877	19	116	81	27	2 184	35	25	877	19
April	126	84	26	2 187	42	23.3	978	10.5	126	87	26	2 261	39	23.2	905	10.5
May	130	91	24.4	2 222	39	23.8	930	15	144	93	24.4	2 270	51	24.1	1228	16
June	123	88	23.7	2 089	35	24.5	858	13.9	137	87	23.7	2 065	50	24.4	1221	13.9
July	123	89	23.7	2 112	34	25.3	861	14	131	98	23.7	2 327	33	25.1	835	13
August	112	79	24.1	1 907	33	26.2	863	17	116	80	24.1	1 932	36	26.2	943	18
September	110	76	25	1 902	34	26.6	906	17	112	80	25.1	2 007	32	26.7	856	17
October	110	76	26	1 978	34	27.6	940	18	123	91	26.2	2 385	32	27.8	891	18
November	104	70	26.9	1 881	34	28.1	955	18	118	84	27	2 272	34	28.2	959	18
December	110	75	27.6	2 068	35	27.7	971	18	119	82	27.7	2 268	37	27.8	1029	18
Mean	116	81	25.8	2 078	35	25.9	914	16.5	123	86	25.8	2 205	37	26	966	16.6
SD	8	6.3	1.5	132	3	1.6	43	2.7	10	5.9	1.5	136	6	1.6	132	2.8
Month	IR64								TXD306
	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI	Day_whole	Day_pre	MT_pre	AT_pre	Day_post	MT_post	AT_post	T_MinPI
	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)	(d)	(d)	(ºC)	(ºC)	(d)	(ºC)	(ºC)	(ºC)
January	123	87	27.5	2 394	36	26.9	967	18	134	100	27.4	2 743	34	26.5	901	19
February	138	102	27.3	2 783	36	25.3	911	19	146	109	27.2	2 961	37	25	924	19
March	125	90	26.8	2 414	35	24.6	863	18	147	113	26.4	2 987	34	23.1	785	10.5
April	147	108	25.4	2 748	39	23.3	908	14	155	118	25.2	2 971	37	23.7	878	14
May	141	101	24.4	2 460	40	24.1	964	13	154	118	24.2	2 855	36	24.5	883	13.9
June	139	103	23.9	2 458	36	24.4	878	17	151	117	24	2 803	34	24.7	838	14
July	140	105	23.8	2 498	35	25.7	901	15	152	117	23.9	2 795	35	26.2	917	18
August	130	97	24.5	2 377	33	26.5	874	18	145	112	24.7	2 771	33	26.8	885	17
September	125	89	25.2	2 242	36	27	973	18	145	110	25.5	2 808	35	27.6	966	18
October	123	88	26.2	2 304	35	27.8	973	18	144	110	26.5	2 918	34	28.2	957	18
November	118	83	27	2 245	35	28.2	986	18	134	99	27.2	2 690	35	27.8	974	18
December	125	90	27.7	2 492	35	27.8	974	18	135	101	27.6	2 787	34	27.6	939	18
Mean	131	95	25.8	2 451	36	26	931	17	145	110	25.8	2 841	35	26	904	16.5
SD	9	8.3	1.5	171	2	1.6	46	1.9	7	7	1.4	97	1	1.7	55	2.7

Month	NERICA1 (kg/m²)				Wahiwahi (kg/m²)				IR64 (kg/m²)				TXD306 (kg/m²)				Mean rank
Month	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y
January	1.38	0.16	1.54	0.39	1.59	0.39	1.98	0.45	1.01	0.61	1.62	0.29	1.81	0.29	2.1	0.17	5	7.8	7	8.5
February	1.08	0.61	1.68	0.45	1.73	0.39	2.13	0.54	1.45	0.81	2.26	0.43	1.44	0.19	1.63	0.28	5.3	6.8	5.3	5.5
March	1.57	0.41	1.98	0.37	2.12	0.47	2.59	0.38	1.19	1.04	2.23	0.57	1.25	0.33	1.59	0.2	5.8	5.5	3.8	7
April	1.15	0.73	1.89	0.31	1.61	0.91	2.52	0.07	1.57	0.42	1.99	0.19	1.5	0.11	1.61	0.22	4.5	6.3	5.3	10.5
May	1.3	0.7	1.99	0.37	1.32	1	2.32	0.02	1.4	0.31	1.71	0.15	1.79	0.43	2.22	0.38	4.8	4.8	3	9.8
June	1.21	0.77	1.97	0.53	1.26	0.7	1.96	0.05	1.29	0.79	2.07	0.46	1.63	0.54	2.18	0.62	6.8	2.3	4.3	5.3
July	1.21	0.77	1.98	0.53	1.52	0.38	1.9	0.5	1.68	0.44	2.13	0.57	1.69	0.45	2.14	0.5	4	5.5	4.5	2.5
August	0.97	0.09	1.07	0.39	0.95	0.46	1.41	0.55	1.35	0.3	1.65	0.42	1.11	0.21	1.32	0.48	10.5	9	11.3	4.5
September	0.76	0.48	1.24	0.36	1.04	0.39	1.43	0.41	1.53	0.29	1.82	0.53	1.15	0.44	1.58	0.4	9.3	7.5	9.5	6.3
October	1.05	0.18	1.23	0.21	1.5	0.34	1.84	0.33	1.28	0.22	1.5	0.48	1.46	0.2	1.66	0.25	7.8	10.8	10	8.8
November	1.04	0.42	1.46	0.37	1.71	0.53	2.24	0.61	1.39	0.21	1.6	0.51	1.35	0.43	1.78	0.37	6.8	7.3	7.5	5
December	0.99	0.83	1.83	0.54	1.4	0.54	1.94	0.51	1.2	0.5	1.71	0.32	1.71	0.21	1.91	0.43	7.8	4.8	6.8	4.5
Mean	1.14	0.51	1.65	0.4	1.48	0.54	2.02	0.37	1.36	0.5	1.86	0.41	1.49	0.32	1.81	0.36
SD	0.21	0.26	0.34	0.1	0.32	0.22	0.37	0.21	0.18	0.26	0.26	0.14	0.24	0.14	0.29	0.14
P-value																	0.25	0.122	0.014	0.046

Month	NERICA1 (kg/m²)				Wahiwahi (kg/m²)				IR64 (kg/m²)				TXD306 (kg/m²)				Mean rank
Month	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y	DW_pre	DW_post	DW_whole	Y
January	1.38	0.16	1.54	0.39	1.59	0.39	1.98	0.45	1.01	0.61	1.62	0.29	1.81	0.29	2.1	0.17	5	7.8	7	8.5
February	1.08	0.61	1.68	0.45	1.73	0.39	2.13	0.54	1.45	0.81	2.26	0.43	1.44	0.19	1.63	0.28	5.3	6.8	5.3	5.5
March	1.57	0.41	1.98	0.37	2.12	0.47	2.59	0.38	1.19	1.04	2.23	0.57	1.25	0.33	1.59	0.2	5.8	5.5	3.8	7
April	1.15	0.73	1.89	0.31	1.61	0.91	2.52	0.07	1.57	0.42	1.99	0.19	1.5	0.11	1.61	0.22	4.5	6.3	5.3	10.5
May	1.3	0.7	1.99	0.37	1.32	1	2.32	0.02	1.4	0.31	1.71	0.15	1.79	0.43	2.22	0.38	4.8	4.8	3	9.8
June	1.21	0.77	1.97	0.53	1.26	0.7	1.96	0.05	1.29	0.79	2.07	0.46	1.63	0.54	2.18	0.62	6.8	2.3	4.3	5.3
July	1.21	0.77	1.98	0.53	1.52	0.38	1.9	0.5	1.68	0.44	2.13	0.57	1.69	0.45	2.14	0.5	4	5.5	4.5	2.5
August	0.97	0.09	1.07	0.39	0.95	0.46	1.41	0.55	1.35	0.3	1.65	0.42	1.11	0.21	1.32	0.48	10.5	9	11.3	4.5
September	0.76	0.48	1.24	0.36	1.04	0.39	1.43	0.41	1.53	0.29	1.82	0.53	1.15	0.44	1.58	0.4	9.3	7.5	9.5	6.3
October	1.05	0.18	1.23	0.21	1.5	0.34	1.84	0.33	1.28	0.22	1.5	0.48	1.46	0.2	1.66	0.25	7.8	10.8	10	8.8
November	1.04	0.42	1.46	0.37	1.71	0.53	2.24	0.61	1.39	0.21	1.6	0.51	1.35	0.43	1.78	0.37	6.8	7.3	7.5	5
December	0.99	0.83	1.83	0.54	1.4	0.54	1.94	0.51	1.2	0.5	1.71	0.32	1.71	0.21	1.91	0.43	7.8	4.8	6.8	4.5
Mean	1.14	0.51	1.65	0.4	1.48	0.54	2.02	0.37	1.36	0.5	1.86	0.41	1.49	0.32	1.81	0.36
SD	0.21	0.26	0.34	0.1	0.32	0.22	0.37	0.21	0.18	0.26	0.26	0.14	0.24	0.14	0.29	0.14
P-value																	0.25	0.122	0.014	0.046

Month	NERICA1				Wahiwahi				IR64				TXD306				Mean rank
Month	P	S	F (%)	G (g)	P	S	F (%)	G (g)	P	S	F (%)	G (g)	P	S	F (%)	G (g)	P	S	F	G
January	333	81.5	53.7	26.7	350	43.6	94.2	31.3	510	52.3	43.4	24.6	400	30.8	51.4	26.9	5.3	8.5	8.5	8
February	243	89.1	77.5	27	280	71.1	81.3	33.3	493	51.1	65.5	26.1	277	63.3	59.3	26.7	9.5	3	6	5
March	200	86.9	79.3	26.9	253	67.4	71.2	31.6	400	84.4	64.2	26.1	270	52.9	68.9	29.6	11.5	3.8	5.5	4.5
April	293	50	77.8	27	260	80.8	10.2	32.3	587	33.2	39.2	24.7	333	53.8	46.6	26.7	7.5	8	9.8	7
May	307	68.3	65.5	26.6	423	60	2.2	30.1	423	50.5	30.6	23.3	333	62.2	68	27.1	6.3	6.5	10	8.8
June	313	81.5	75.4	17.2	727	60.8	3.6	32.4	480	56	66.3	25.6	380	76.1	75.5	28.3	5.3	3.8	4.8	6.3
July	360	78.9	66.5	28.1	407	50.8	70.2	34.5	343	70.8	86.5	27.1	333	68.5	76.3	28.6	6.3	5.8	4.8	1.3
August	220	80.3	81.2	27.5	357	66.5	72.1	31.9	387	73.9	60	24.3	413	56.5	72.1	28.3	7.8	5	5	5.8
September	273	82.1	89.5	17.8	307	58.5	70.1	32.6	570	48.1	71.2	27	387	61.4	61.8	26.9	7	6.3	5.3	6.3
October	253	43.4	73.6	25.8	317	58.3	61.8	28.6	727	40.8	67	24.4	497	35.7	55.2	25	4.8	10.5	7.8	10.8
November	320	64.1	69	26.1	423	66.9	72.2	29.6	597	48.2	76.1	23.2	480	42.6	66.7	27	2.8	7.8	5.3	9.8
December	360	62.1	86.8	27.6	393	52.8	75.5	32.8	617	38.9	52.3	25.1	403	61.2	64	27.2	3	9.3	5.5	4
Mean	290	72.4	74.7	25.4	375	61.5	57.1	31.8	511	54	60.2	25.1	376	55.4	63.8	27.4
SD	52	14.7	9.9	3.7	126	9.9	32.2	1.7	113	15.2	16.1	1.3	71	13.3	9.4	1.2
P-value																	0.034	0.062	0.296	0.014