Americas and Oceania Group - International Plant Nutrition Institute

Global Maize Project in Russia: N. Tselina, Rostov Oblast
Project Leader: O.A. Biryukova, Southern Federal University Department of Soil Science and Land Resources
Evaluation, Rostov-on-Don, Rostov Oblast. E-mail: olga_alexan@mail.ru
Project Cooperator: D.V. Bozhkov
Maize was grown in 2011 after winter wheat at both the A-site and C-site. The potential yield was
determined at the A-site, and thus the respective yield gap. We accessed what practices and inputs needed
to be modified to narrow the yield gap. The current grower practice and the Ecological Intensification
(EI) management system were compared for the site. On-farm experiments (C-site) were used to facilitate
fine-tuning of the management systems and getting them in place on farmers’ fields. Initial soil properties
indicate substantial soil nitrate (14.1 to 14.6 ppm in 0 to 20 cm layer), medium P extracted by a routine soil
test (1% (NH 4 ) 2 CO 3 )—or “increased” (16 ppm P) according to new Olsen P soil-test interpretation classes
proposed by researchers in Russia. The content of K extracted by 1% (NH 4 ) 2 CO 3 was considered high, and the
exchangeable K level was very high (373 to 387 ppm).
Grower fertilizer practice for maize (30 N 40 P) gave 8.12 t/ha grain at the A-site and “omission” of N
fertilizer (9 N 40 P) resulted in 7.78 t/ha. No real zero N plots were tested since monoammonium phosphate
(MAP) was used as a source of P. Ecological Intensification (EI) for maize (80 N 70 P 40 K) gave 8.77 t/
ha, and “omission” of N (12 N 70 P 40 K) resulted in 8.33 t/ha. Grower fertilizer practice for soybean (20 N
40 P) gave 1.92 t/ha at the A-site, and “omission” of N fertilizer (9 N 40 P) produced 1.86 t/ha. In soybean,
EI (30 N 45 P 30 K) gave 2.27 t/ha, while “omission” of N (10 N 45 P 30 K) led to 2.12 t/ha. Ecological
Intensification for soybean also resulted in higher protein content in grain (46.7%) compared with N
“omission”(43.9%)—generating a maximum protein output of 1,060 kg/ha. The highest yield of maize at the
C-site (8.98 t/ha) was obtained with ample NPK rates (100 N 80 P 60 K) and the control treatment gave 7.45
t/ha. Thus, maize yield increased by 21% due to mineral fertilizer application. Nitrogen, P, and K fertilizer
use at the C-site increased grain yield by 0.69 t/ha (8%), 1.05 t/ha (13%), and 0.56 t/ha (7%), respectively.
Response to K fertilizer application indicates that perhaps soil-test K interpretation classes need to be adjusted
and updated. IPNI-41
Global Maize Project in Mexico: Celaya, Guanajuato
Project Leader: Roberto Paredes, Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP),
Colonia Roque Celaya, Guanajuato. E-mail: rparedesm59@prodigy.net.mx, paredes.roberto@inifap.gob.mx
Project Cooperator: Benjamin Zamudio
The study was started in 2009 in Celaya, State of Guanajuato, Mexico, at 1,830 meters above sea level. The
treatment design included a combination of two management systems (plant populations) (Farmers’ practice
[FP] and a higher population [EI]) and three N fertilization regimes (0-N, 300 kg N/ha applied two out of
three years, and 300 kg N/ha applied every year). In 2011, the six treatments were: 1) 120,192 seeds/ha, 0-N;
2) 120,192 seeds/ha, 300 kg N/ha (0 N in 2009; 300 kg N/ha in 2010); 3) 120,192 seeds/ha, 300 kg N/ha (300
kg N/ha applied both in 2009 and 2010); 4) 90,580 seeds/ha, 0-N; 5) 2) 90,580 seeds/ha, 300 kg N/ha (0-N in
2009; 300 kg N/ha in 2010); 6) 90,580 seeds/ha, 300 kg N/ha (300 kg N/ha applied both in 2009 and 2010).
The first three treatments are considered as an intensification of the last three, which represent the traditional
farmers’ practice.
Yields responded to N, regardless of its application sequence. The application of 300 kg N/ha increased
grain yields from an average of 1.9 t/ha to 10.9 t/ha, a reflection of significantly greater Harvest Index, more
ears/ha, and larger ears with heavier kernels. Partial Factor Productivity and Agronomic Efficiency were 36
and 30 kg grain/kg N, respectively. No significant differences in grain yield could be detected between the
intensive and traditional management options, although plant population at harvest differed significantly
between them: 91,600 vs. 68,900 plants/ha, respectively. By harvest time, the plant population under both
management systems had decreased by 24% on average, which is higher than normal, especially under
experimental conditions. Most of that loss (15%) had taken place by the third week after crop planting.
IPNI-28
Global Maize Project in Mexico: Toluca, México
Project Leader: Benjamín Zamudio, González Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias
(INIFAP), Toluca, México. E-mail: zamudio.benjamin@inifap.gob.mx
The study was started in 2009 in Toluca, State of México, at an altitude of 2,370 meters above sea
level. The objective was to compare the effects of six combinations of plant populations and fertilizer
applications. Half of the treatments—labeled as intensive management—included high plant populations
and the application of a complete fertilizer formula (90 kg P 2 O 5 /ha, 90 kg K 2 O/ha, 44 kg MgO/ha, 50 kg S/
ha, and 3 kg Zn/ha). The remaining treatments were similar to current farmers’ practices with regards to plant
IPNI Interpretive Summaries 11