Sex: Female

Education:

• Chiba University, Chiba, Japan, Doctor of Philosophy in Soil Science, 2006 S
• University of the Philippines at Los Baños, College, Los Baños Laguna, MS Agricultural Chemistry, 1981
• University of Santo Tomas, España, Manila, BS Chemistry, 1975

Field of Specialization:

Agricultural Chemistry, Soil Health Science

Researches:

Ladha, J.K., Padre, A.T., (2004) Assessing the reliability of permanganate-oxidizable C as an index of soil labile C
Soil Science Society of America Journal Volume 68, No. 3

Tsuchiya, K., Inubushi, K., Ladha, J.K., (2005) Enhancing soil quality through residue management in a rice-wheat system in Fukuoka, Japan
Soil Science Plant Nutrition Volume 51, No. 6

Padre, A.T., Ladha, J.K., (2006) Integrating rice and wheat productivity trends using SAS mixed-procedure and meta-analysis
Field Crops Research Volume 95, No. 1

Ladha J.K., Dawe, D., Pathak, H., Yadav, R.L., Singh, B., Singh, Y., Singh, P., Kundu, A.L., Sakal, R., Ram, N., Regmi, A.P., Gami, S.K., Bhandari, A.L., Amin, R., Yadav, C.R., Bhattarai, E.M., Das, S., Aggarwal, H.P., Gupta, R.K., Hobbs, P.R., (2003) How extensive are yield declines in long-term rice-wheat experiments in Asia?
Field Crops Research Volume 81

Sharma P.K., Ladha, J.K., Verma, T.S., Bhagat, R.M., (2003) Rice-wheat productivity and nutrient status in a lantana (Lantana spp.) amended soil
Biol. Fertil. Soils Volume 37

Tirol-Padre, A., Ladha, J. K., Singh, U., Laureles, E., Punzalan, G. and Akita, S., (1996) Grain yield performance of rice genotypes at suboptimal levels of soil N as affected by N uptake and utilization efficiency.
Field Crops Res. Volume 46(1-3)

Padre, A. T., (1981) Mineralization of blue-green algal nitrogen in a rice paddy soil and its availability to the rice plant
MS Thesis

Padre, A. T., () Managing C and N for sustaining soil quality and productivity of rice in rice-rice and rice-wheat systems
PhD Dissertation

Tirol-Padre, A., Ladha, J.K., Regmi, A.P., Bhandari, A.L., Inubushi, K., (2007) Organic amendments affect soil parameters in two long-term rice-wheat experiments
Soil Science Society of America Journal Volume 71

Tirol-Padre, A., Ladha, J.K., (1990) Effect of planting method and optimum seeding rate on biomass production and nitrogen fixation in Sesbania rostrata
International Rice Research Newsletter Volume 15

Tirol-Padre, A., J. K., Ladha, Punzalan, G. C. and Watanabe, I. , (1988) A plant sampling procedure for acetylene reduction assay to detect rice varietal differences in ability to stimulate N2 fixation
Soil Biol. Biochemistry Volume 20

Tirol, A.C., Roger, P. A., Watanabe, I., (1982) Fate of nitrogen from a blue-green alga in a flooded rice soil
Soil Science Plant Nutrition Volume 28, No. 4

Tirol, A.C., Santiago, S.T., Watanabe, I., (1981) Effect of the insecticide carbofuran on microbial activities in flooded soil
Journal of Pest. Science Japan Volume 6

Haefele, S.M., Jabbar, S.M.A., Siopongco, J.D.L.C. , Tirol-Padre, A., Amarante, S.T., Sta Cruz, P.C., Cosico, W.C., (2008) Nitrogen use efficiency in selected rice (Oryza sativa L.) genotypes under different water regimes and nitrogen levels
Field Crops Research Volume 107

Bhushan, L., Ladha, J.K., Gupta, R.K., Singh, S., Tirol-Padre, A., Sahrawat, Y.S., Gathala, M., Pathak, H., (2007) Saving of water and labor in rice-wheat system with no-tillage and direct seeding technologies
Agronomy Jounal Volume 99

Ladha J.K., D. Dawe, H. Pathak, A.T. Padre, R.L. Bijay Singh, Y., Singh, Y., Singh, Y., Singh, P., Kundu, A. L., Sakal, R., Ram, N., Regmi, A.P., Gami, S. K., Bhandari, A.L., Amin, R., Yadav, C. R., Bhattarai, E. M., Das, S., Aggarwal, H. P.,Gupta, R. K., Hobbs, P. R., (2003) How extensive are yield declines in long-term rice-wheat experiments in Asia?
Field Crops Res. Volume 81

Sharma, P.K., Ladha, J.K., Verma, T. S., Bhagat, R. M. and Padre, A. T., (2003) Rice-wheat productivity and nutrient status in a lantana (Lantana spp.) amended soil
Biol. Fertil. Soils Volume 37

Chalk, P.M., Ladha, J. K. and Padre, A. T., (2002) Efficacy of three 15N labelling techniques for estimating below-ground N in Sesbania rostrata
Biol. Fertil. Soils Volume 35

Bhandari, A.L., Ladha, J.K., Pathak, H., Padre, A.T., Dawe, D. and Gupta, R. K., (2002) Yield and soil nutrient changes in a long-term rice-wheat rotation in India
Soil Sci. Soc. Am. J. Volume 66

Pascua, S.R., Ventura, W., Agustin, E.O., Padre, A. T., Valencia, D. A., Marcos, T. F., Sta. Cruz, P.C., Obien, S. R., Ladha, J. K., (1999) Yield trends and apparent nutrient balances in intensified and diversified rice-based cropping systems of Ilocos Norte, Philippines
Experimental Agriculture Volume 35

Agustin, E.O., Ortal, C.I., Pascua, S.R., Sta. Cruz, P.C., Padre, A.T., Ventura, W., Obien, S.R., Ladha, J. K., (1999) Role of Indigo (Indigofera tinctoria) in improving the productivity of rainfed lowland rice-based cropping systems
Experimental Agriculture Volume 35

Ladha, J.K., Tirol-Padre, A., Punzalan, G., Castillo, E., Singh, U. and Reddy, C. K. , (1998) Non-destructive estimation of shoot nitrogen at flowering stage in different rice genotypes
Agron. J. Volume 90

Sahu, R.K., Tirol-Padre, A., Ladha, J. K., Singh, U., Baghel, S.S., Shrivastava, S. S., (1997) Screening genotypes for nitrogen use efficiency on a nitrogen deficient soil.
Oryza Volume 34

Singh, U., Ladha, J. K., Castillo, E. G., Punzalan, G., Tirol-Padre, A. and Duqueza, M., (1997) Genotypic variation in nitrogen use efficiency in medium-and long duration rice
Field Crops Res. Volume 68

Ladha J. K., Tirol-Padre, A., Punzalan, G. Garcia, M. and Watanabe, I., (1989) Effect of inorganic N and organic fertilizers on nitrogen-fixing (acetylene-reducing) activity associated with wetland rice plants
In: F. A. Skinner et al. (Eds.) Nitrogen fixation with non-legumes, Kluwer Academic Publishers

Ladha, J.K., Garcia, M., Miyan, S., Padre, A. T., and Watanabe, I., (1989) Survival of Azorhizobium caulinodans in soil and rhizosphere of wetland rice under Sesbania rostrata- rice rotation
Appl. Environ. Microb. Volume 55

Ladha, J.K., Tirol-Padre, A., Daroy, M. L. G., Punzalan, G. and Watanabe, I., (1987) The effects on N2 fixation (C2H2 reduction), bacterial population and rice plant growth of two modes of straw application to a wetland rice field
Biol. Fertil. Soils Volume 5(2)

Ladha, J.K., Tirol-Padre, A., Punzalan, G. C. and Watanabe, I., (1987) Nitrogen-fixing (C2H2-reducing) activity and plant growth characters of 16 wetland rice varieties
Soil Sci. Plant Nutr. Volume 33(2)

Roger, P.A., Tirol, A.C., Ardales, S. and Watanabe, I., (1986) Chemical composition of cultures and natural samples of N2-fixing blue-green algae from rice fields
Biol. Fertil. Soils Volume 2(3)

Ladha, J. K., Tirol, A. C., Daroy, M. L. G., G. Caldo, G., Ventura, W. B., Watanabe, I., (1986) Plant-associated N2-fixation (C2H2-reduction) by five rice varieties, and relationship with plant growth characters as affected by straw incorporation
Soil Science Plant Nutrition Volume 32

Ladha, J. K., Tirol, A. C., Caldo, G., and Watanabe, I. , (1986) Rice plant-associated N2-fixation as affected by genotype, inorganic fertilizer, and organic manure
In: Trans. XIII Congress of the International Society of Soil Science, Hamburg Volume 2

Barraquio, W.L., Daroy, M.L., Tirol, A.C., Ladha, J.K. and Watanabe, I., (1986) Laboratory acetylene reduction assay for relative measurement of N2-fixing activities associated with field-grown wetland rice plants
Plant Soil Volume 90

App, A. A., Santiago, S. T., Daez, C., Menguito, C., Ventura, W. B., Tirol, A. C., Po, J., Watanabe, I., De Datta, S. K. and Roger, P. A., (1984) Estimation of the nitrogen balance for irrigated rice and the contribution of phototrophic nitrogen fixation
Field Crops Research Volume 9

Grant, I.F., Tirol, A.C., Aziz, T., Watanabe, I., (1983) Regulation of invertebrate grazers as a means to enhance biomass and nitrogen fixation of Cyanophycea wetland rice fields
Soil Science Society of America Journal Volume 47

Roger, P.A., Kulasooriya, S.A., Tirol, A.C., Craswell, E.T., (1981) Deep placement: A method of nitrogen fertilizer application compatible with algal nitrogen fixation in wetland rice soils
Plant and Soil Volume 57

Siddaramappa, R.A., Tirol, A. C., Seiber, J. Heinrichs, N.E. A., and I. Watanabe, I., (1978) The degradation of carbofuran in paddy water and flooded soil of untreated and retreated rice fields
J. Environ. Sci. Health Volume B13

Gaihre, Y.K., Tirol-Padre, A., Wassmann, R., et al., (2012) Spatial and Temporal Variations in Methane Fluxes from Irrigated Lowland Rice Fields
The Philippine Agricultural Scientist Volume 94, No. 4

Ladha, J.K., Reddy, C.K., Padre, A.T. et al., (2011) Role of nitrogen fertilization in sustaining organic matter in cultivated soils
Journal of Environmental Quality Volume 40, No. 6

Tirol-Padre, A., Ladha, J.K., Regmi, P. et al., (2007) (2007) Organic Amendments Affect Soil Parameters in Two Long-Term Rice-Wheat Experiments
Soil Science Society of America Journal Volume 71, No. 2

Arvind K. Shukla, Jagdish K. Ladha, V. K. Singh, B. S. Dwivedi, Vethaiya Balasubramanian, Raj K. Gupta, S. K. Sharma, Yogendra Singh, H. Pathak, P. S. Pandey, Agnes T. Padre, R. L. Yadav, (2004) Calibrating the Leaf Color Chart for Nitrogen Management in Different Genotypes of Rice and Wheat in a Systems Perspective
Journal of Environmental Quality Volume 96, No. 6

Ladha, J.K., Padre, A.T., Nayak, D.N. et al., (1986) Nitrogen fixation by single and mixed heterotrophic bacteria in flooded paddy soils amended with hydrogen peroxide treated straw (hemicellulose)
Proceedings of the IV International Symposium of Microbial Ecology, Aug 24-29, 1986, Ljubljana, Yugoslavia.

Tirol-Padre, A., Ladha, J.K., (2006) Integrating rice and wheat productivity trends using the SAS mixed-procedure and meta-analysis
Field Crops Research Volume 95, No. 1

Ladha, J.K., Pathak, H., Tirol-Padre, A.et al., (2003) Productivity trends in intensive rice-wheat cropping systems in Asia
ASA Special Publication Number 65.