- Pitkin, Linda M
- Pitkow, Ronald B
- Pitman, C. B.
- Pitman, Charles Charles Robert Senhouse Pitman 1890-1975
- Pitman, Charles Edward
- Pitman, Emma Raymond
- Pitman, James C
- Pitman, Janet K.
- Pitman, John H
- Pitman, M. R. P. L.
- Pitman, Michael
- Pitman, Nigel
- Pitman, Nigel C A
- Pitman, Robert L
- Pitman, Sheryn
- Pitman-Moore, Inc.
- Pitney, Kenneth.
- Pitocchelli, Jay
- Pitogo, Kier Mitchel
- Pitol, DL.
- Pitombo, Fábio B.
- Pitopang, Ramadanil
- Pitrat, M
- Pitrè, Giuseppe, 1841-1916
- Pitriana, Pipit
- Pitsko, Leigh
- Pitt, A
- Pitt, Elizabeth.
- Pitt, Frances, 1888-1964
- Pitt, Jerome
- Pitt, Justin A.
- Pitt, L J
- Pitt, Leslie John
- Pitt, Lois J
- Pitt, Michael D.
- Pitt, W. E.
- Pitt, William C.
- Pitt, William D
- Pitt, William, 1749-1823
- Pitta Groz, Maria
- Pitta, Iara Regina Cardoso
- Pittam, Sherry K.
- Pittao, Elena
- Pittara, Marilena
- Pittaway, A R
- Pittaway, Lois A
- Pittaway, Ronald Jr.
- Pittendrigh, C S
- Pittendrigh, Colin S
- Pittenger, J. W.
- Pittenger, J.W. (Firm : Nampa, Idaho)
- Pittfield, Taryn
- Pittie, A
- Pittie, Aasheesh
- Pittier, Emilio,
- Pittier, Henri, 1857-1950
- Pittillo, Dan
- Pittino, R
- Pittino, Riccardo
- Pittioni, B
- Pittman & Harrison Co.
- Pittman & Harrison Company.
- Pittman and Harrison Co.
- Pittman, A B
- Pittman, A J
- Pittman, Albert B
- Pittman, E F
- Pittman, E. F. (Edward Fisher), 1849-
- Pittman, H A
- Pittman, H. H.
- Pittman, J L
- Pittman, Michael, 1985-
- Pittman, R. N.
- Pittman, Shannon E.
- Pittman, Stuart
- Pittman, Tony
- Pittman-Robertson Project (Mont.)
- Pittock, Glenna.
- Pitts, Brenda
- Pitts, David
- Pitts, James
- Pitts, James P
- Pitts, John P
- Pitts, Marjorie W
- Pitts, R M
- Pitts, R O
- Pitts, Raymond C., 1957-
- Pitts, Robert F
- Pitts, Stephen
- Pitts, T David
- Pittsburgh Nurseries.
- Pitwell, L R
- Pitysmont Nurseries.
- Pitz, Kevin M
- Pitzonka's Pansy Farm and Nursery.
- Pitzonka's Pansy Farm.
- Piudo, Luciana
- Piva, Lucas
- Pivar, Robert
- Pivari, Marco Otávio Dias
- Pivello, Vânia
- Pivello, Vânia R.
- Pivello, Vânia Regina
- Pivello, VR.
- Piveta, Graziela
- Piveteau, J
- Pivkin, M V
- Piwnik, Agata
- Piwowarczyk, Renata
- Pix, Frantiek
- Piyatrakulchai, Paveen
- Piza, Isabela Miranda de Toledo
- Pizá, Julia
- Piza, M. A.
- Pizango-Paima Emer Gloria
- Pizani, N V
- Pizarro Araya, Jaime Rodrigo
- Pizarro Domínguez, José María
- Pizarro, Desirree
- Pizarro, Gemita
- Pizarro, H
- Pizarro, H N
- Pizarro, Haydée E.
- Pizarro, J. Cristóbal
- Pizarro, Jaime
- Pizarro, Jessica
- Pizarro, Jose Cristóbal
- Pizarro, Juliana
- Pizarro, Marlene
- Pizarro, Natalia
- Pizarro, O.
- Pizarro, Oscar
- Pizarro, R
- Pizarro, Roberto
- Pizarro, Rodrigo
- Pizarro, Valeria
- Pizarro, Vanessa
- Pizarro, Yemmy Paredes
- Pizarro-Mora, Felipe
- Pizcueta y Donday, José
- Pizey, R M
- Pizinger, Donald D.
- Pizo, Marco Aurélio
- Pizon, A
- Pizon, Antoine
- Pizzaia, Daniel
- Pizzetta, Jules, 1820-1900
- Pizzetti, Daniela
- Pizzini, M
- Pizzini, Mauro
- Pizzo, Giuseppina Musarra
- Pizzolato, Thompson Demetrio.
- Pizzoloto, Roberto
- Pizzolotto, Roberto
- Pizzorno, José L.
- Pkhakadze, Vera
- Plá Puchulu, Natalia
- Plá y Rave, Eugenio
- Pla, Laura
- Plaat, C.
- Place, A E
- Place, Francis, 1647-1728
- Place, Frank
- Place, J A
- Placer Nurseries.
- Plachno, Bartosz J
- Placho, Giorgio (Rome)
- Plachte, Frank Lothar, 1913-
- Plachter, H
- Plachter, Harald
- Placitus, Sextus, Papyriensis.
- Placzek, Christa
- Pladeck, Mildred
- Plageman, R. B. (Rudolph B.)
- Plagens, Michael Joseph, 1954-
- Plaia, P.
- Plăiaşu, Rodica
- Plain City Greenhouses.
- Plainer, R M
- Plainfield Nursery (Scotch Plains, N.J.)
- Plainfield Nursery (Scotch Plains, N.J.).
- Plainview Nursery.
- Plair, Bernadette L
- Plakhov, Nikita, 1758-1804
- Plakidas, J D
- Plakidas, John D
- Plamboeck, Agneta H
- Plana, Jordi
- Plana, Jorge
- Plana-Fattori, Artemio
- Planas, Dolores
- Planas, Enric
- Planas, Eulalia
- Planas, Juan
- Planas, Miquel
- Planchard, F
- Planchon, G. (Gustave), 1833-1900
- Planchon, Jules-Emile, 1823-1888
- Planchon, Louis, 1858-1915
- Planchuelo, A M
- Planchuelo, Ana M.
- Planchuelo, Ana Maria
- Planck, R. J.
- Plane, M
- Planella, M. Teresa
- Planellas Giralt, José
- Planelles, Gabrielle
- Planer, Johann Jakob, 1743-1789
- Planer, Julius, 1827-1881
- Planes, S
- Planes, Serge
- Planet, Louis.
- Planetary Biodiversity Inventory (Project)
- Plangg, R.
- Plank, Andreas
- Plank, C. A.
- Plank, Elisha N.
- Plank, H. K. (Harold Kaufman), 1891-
- Plank, Heidi.
- Plank, Marlin E.
- Plank, Robert Northey.
- Plankton Expedition 1889-
- Plannck, Stephan, active 15th century-
- Planning and Training Conference for Insect Nutrition and Rearing Excelsior Springs, Mo.) 1963-
- Planning and Training Conference for Insect Pathology and Biological Control Excelsior Springs, Mo.) 1964-
- Planning and Training Conference for Insect Population Suppression Memphis, Tenn.) 1965-
- Planoutene, M
- Planquette, P
- Plant Brothers.
- Plant Conservation Alliance.
- Plant Gene Resources of Canada. Seed Genebank.
- Plant Genetics and Germplasm Institute.
- Plant Materials Program (U.S.)
- Plant Nematology Workshop North Carolina State College) 1954-
- Plant Protection Laboratories (U.S.)
- Plant Research Centre (Canada)
- Plant Research Institute (Canada)
- Plant Seed Co.
- Plant Seed Co. (St. Louis, Mo)
- Plant Seed Company (Saint Louis, Mo.)
- Plant Seed Company.
- Plant Stress Laboratory.
- Plant World Association.
- Plant, Adrian R.
- Plant, Alfred.
- Plant, Colin W.
- Plant, Fred S.
- Plant, John
- Plant, R A
- Plant, R J